diff --git a/scripts/run.sh b/scripts/run.sh
index d2d8115..37ea655 100755
--- a/scripts/run.sh
+++ b/scripts/run.sh
@@ -237,7 +237,7 @@ fi
 # Get species data per taxa from IUCN data
 for TAXA in "${TAXAS[@]}"
 do
-    if [ ! -f "${DATADIR}"/overrides.csv ]; then
+    if [ -f "${DATADIR}"/overrides.csv ]; then
         python3 ./prepare_species/extract_species_psql.py --class "${TAXA}" \
                                                         --output "${DATADIR}"/species-info/"${TAXA}"/ \
                                                         --projection "EPSG:4326" \
@@ -259,7 +259,7 @@ python3 ./utils/persistencegenerator.py --datadir "${DATADIR}" \
                                         --scenarios "${SCENARIOS[@]}"
 
 # Calculate all the AoHs
-littlejohn -j 700 -o "${DATADIR}"/aohbatch.log -c "${DATADIR}"/aohbatch.csv aoh-calc -- --force-habitat
+littlejohn -j 30 -o "${DATADIR}"/aohbatch.log -c "${DATADIR}"/aohbatch.csv "${VIRTUAL_ENV}"/bin/aoh-calc -- --force-habitat
 
 # Generate validation summaries
 aoh-collate-data --aoh_results "${DATADIR}"/aohs/current/ --output "${DATADIR}"/aohs/current.csv
@@ -277,7 +277,7 @@ aoh-endemism --aohs_folder "${DATADIR}"/aohs/current/ \
              --output "${DATADIR}"/predictors/endemism.tif
 
 # Calculate the per species Delta P values
-littlejohn -j 200 -o "${DATADIR}"/persistencebatch.log -c "${DATADIR}"/persistencebatch.csv "${VIRTUAL_ENV}"/bin/python3 --  ./deltap/global_code_residents_pixel.py
+littlejohn -j 30 -o "${DATADIR}"/persistencebatch.log -c "${DATADIR}"/persistencebatch.csv "${VIRTUAL_ENV}"/bin/python3 --  ./deltap/global_code_residents_pixel.py
 
 for SCENARIO in "${SCENARIOS[@]}"
 do
diff --git a/scripts/slurm.sh b/scripts/slurm.sh
index e3db904..2b89169 100644
--- a/scripts/slurm.sh
+++ b/scripts/slurm.sh
@@ -8,6 +8,7 @@
 # https://github.com/quantifyearth/littlejohn - used to run batch jobs in parallel
 
 set -e
+set -x
 
 # shellcheck disable=SC1091
 source "${HOME}"/venvs/life/bin/activate
@@ -26,144 +27,231 @@ fi
 
 declare -a SCENARIOS=("arable" "restore" "restore_all" "urban" "pasture" "restore_agriculture")
 declare -a TAXAS=("AMPHIBIA" "AVES" "MAMMALIA" "REPTILIA")
-export CURVE=gompertz
+export CURVE=0.25
+export PIXEL_SCALE=0.016666666666667
+
+check_scenario() {
+    local target="$1"
+    for scenario in "${SCENARIOS[@]}"; do
+        if [[ "$scenario" == "$target" ]]; then
+            return 0
+        fi
+    done
+    return 1
+}
 
 
-python3 ./prepare_layers/generate_crosswalk.py --output "${DATADIR}"/crosswalk.csv
+if [ ! -f "${DATADIR}"/crosswalk.csv ]; then
+    python3 ./prepare_layers/generate_crosswalk.py --output "${DATADIR}"/crosswalk.csv
+fi
 
 # Get habitat layer and prepare for use
-reclaimer zenodo --zenodo_id 4058819 \
-                 --filename iucn_habitatclassification_composite_lvl2_ver004.zip \
-                 --extract \
-                 --output "${DATADIR}"/habitat/jung_l2_raw.tif
-
-reclaimer zenodo --zenodo_id 4058819 \
-                 --filename lvl2_changemasks_ver004.zip \
-                 --extract \
-                 --output "${DATADIR}"/habitat/
-
-python3 ./prepare_layers/make_current_map.py --jung "${DATADIR}"/habitat/jung_l2_raw.tif \
-                  --update_masks "${DATADIR}"/habitat/lvl2_changemasks_ver004 \
-                  --crosswalk "${DATADIR}"/crosswalk.csv \
-                  --output "${DATADIR}"/habitat/current_raw.tif \
-                  -j 16
-
-python3 ./aoh-calculator/habitat_process.py --habitat "${DATADIR}"/habitat/current_raw.tif \
-                                            --scale 0.016666666666667 \
-                                            --output "${DATADIR}"/habitat_maps/current/
+if [ ! -f "${DATADIR}"/habitat/current_raw.tif ]; then
+    if [ ! -f "${DATADIR}"/habitat/jung_l2_raw.tif ]; then
+        reclaimer zenodo --zenodo_id 4058819 \
+                        --filename iucn_habitatclassification_composite_lvl2_ver004.zip \
+                        --extract \
+                        --output "${DATADIR}"/habitat/jung_l2_raw.tif
+    fi
+
+    if [ ! -d "${DATADIR}"/habitat/lvl2_changemasks_ver004 ]; then
+        reclaimer zenodo --zenodo_id 4058819 \
+                        --filename lvl2_changemasks_ver004.zip \
+                        --extract \
+                        --output "${DATADIR}"/habitat/
+    fi
+
+    python3 ./prepare_layers/make_current_map.py --jung "${DATADIR}"/habitat/jung_l2_raw.tif \
+                    --update_masks "${DATADIR}"/habitat/lvl2_changemasks_ver004 \
+                    --crosswalk "${DATADIR}"/crosswalk.csv \
+                    --output "${DATADIR}"/habitat/current_raw.tif \
+                    -j 16
+fi
 
-# Get PNV layer and prepare for use
-reclaimer zenodo --zenodo_id 4038749 \
-                 --filename pnv_lvl1_004.zip \
-                 --extract \
-                 --output "${DATADIR}"/habitat/pnv_raw.tif
+if [ ! -d "${DATADIR}"/habitat_maps/current ]; then
+    aoh-habitat-process --habitat "${DATADIR}"/habitat/current_raw.tif \
+                        --scale "${PIXEL_SCALE}" \
+                        --output "${DATADIR}"/habitat_maps/current/
+fi
 
-python3 ./aoh-calculator/habitat_process.py --habitat "${DATADIR}"/habitat/pnv_raw.tif \
-                                            --scale 0.016666666666667 \
-                                            --output "${DATADIR}"/habitat_maps/pnv/
+# Get PNV layer and prepare for use
+if [ ! -f "${DATADIR}"/habitat/pnv_raw.tif ]; then
+    reclaimer zenodo --zenodo_id 4038749 \
+                    --filename pnv_lvl1_004.zip \
+                    --extract \
+                    --output "${DATADIR}"/habitat/pnv_raw.tif
+fi
 
+if [ ! -d "${DATADIR}"/habitat_maps/pnv ]; then
+    aoh-habitat-process --habitat "${DATADIR}"/habitat/pnv_raw.tif \
+                        --scale "${PIXEL_SCALE}" \
+                        --output "${DATADIR}"/habitat_maps/pnv/
+fi
 
 # Generate an area scaling map
-python3 ./prepare_layers/make_area_map.py --scale 0.016666666666667 --output "${DATADIR}"/area-per-pixel.tif
+if [ ! -f "${DATADIR}"/area-per-pixel.tif ]; then
+    python3 ./prepare_layers/make_area_map.py --scale "${PIXEL_SCALE}" --output "${DATADIR}"/area-per-pixel.tif
+fi
 
 # Generate the arable scenario map
-python3 ./prepare_layers/make_arable_map.py --current "${DATADIR}"/habitat/current_raw.tif \
-                                  --output "${DATADIR}"/habitat/arable.tif
-
-aoh-habitat-process --habitat "${DATADIR}"/habitat/arable.tif \
-                    --scale 0.016666666666667 \
-                    --output "${DATADIR}"/habitat_maps/arable/
-
-python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
-                                          --scenario "${DATADIR}"/habitat/arable.tif \
-                                          --area "${DATADIR}"/area-per-pixel.tif \
-                                          --scale 0.016666666666667 \
-                                          --output "${DATADIR}"/habitat/arable_diff_area.tif
+if check_scenario "arable"; then
+    if [ ! -f "${DATADIR}"/habitat/arable.tif ]; then
+        python3 ./prepare_layers/make_arable_map.py --current "${DATADIR}"/habitat/current_raw.tif \
+                                        --output "${DATADIR}"/habitat/arable.tif
+    fi
+
+    if [ ! -d "${DATADIR}"/habitat_maps/arable ]; then
+        aoh-habitat-process --habitat "${DATADIR}"/habitat/arable.tif \
+                            --scale "${PIXEL_SCALE}" \
+                            --output "${DATADIR}"/habitat_maps/arable/
+    fi
+
+    if [ ! -f "${DATADIR}"/habitat/arable_diff_area.tif ]; then
+        python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
+                                                --scenario "${DATADIR}"/habitat/arable.tif \
+                                                --area "${DATADIR}"/area-per-pixel.tif \
+                                                --scale "${PIXEL_SCALE}" \
+                                                --output "${DATADIR}"/habitat/arable_diff_area.tif
+    fi
+fi
 
 # Generate the pasture scenario map
-python3 ./prepare_layers/make_pasture_map.py --current "${DATADIR}"/habitat/current_raw.tif \
-                                             --output "${DATADIR}"/habitat/pasture.tif
-
-aoh-habitat-process --habitat "${DATADIR}"/habitat/pasture.tif \
-                    --scale 0.016666666666667 \
-                    --output "${DATADIR}"/habitat_maps/pasture/
-
-python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
-                                        --scenario "${DATADIR}"/habitat/pasture.tif \
-                                        --area "${DATADIR}"/area-per-pixel.tif \
-                                        --scale 0.016666666666667 \
-                                        --output "${DATADIR}"/habitat/pasture_diff_area.tif
-
-# Generate the restore map
-python3 ./prepare_layers/make_restore_map.py --pnv "${DATADIR}"/habitat/pnv_raw.tif \
-                                   --current "${DATADIR}"/habitat/current_raw.tif \
-                                   --crosswalk "${DATADIR}"/crosswalk.csv \
-                                   --output "${DATADIR}"/habitat/restore.tif
-
-aoh-habitat-process --habitat "${DATADIR}"/habitat/restore.tif \
-                    --scale 0.016666666666667 \
-                    --output "${DATADIR}"/habitat_maps/restore/
-
-python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
-                                          --scenario "${DATADIR}"/habitat/restore.tif \
-                                          --area "${DATADIR}"/area-per-pixel.tif \
-                                          --scale 0.016666666666667 \
-                                          --output "${DATADIR}"/habitat/restore_diff_area.tif
+if check_scenario "pasture"; then
+    if [ ! -f "${DATADIR}"/habitat/pasture.tif ]; then
+        python3 ./prepare_layers/make_pasture_map.py --current "${DATADIR}"/habitat/current_raw.tif \
+                                                    --output "${DATADIR}"/habitat/pasture.tif
+    fi
+
+    if [ ! -d "${DATADIR}"/habitat_maps/pasture ]; then
+        aoh-habitat-process --habitat "${DATADIR}"/habitat/pasture.tif \
+                            --scale "${PIXEL_SCALE}" \
+                            --output "${DATADIR}"/habitat_maps/pasture/
+    fi
+
+    if [ ! -f "${DATADIR}"/habitat/pasture_diff_area.tif ]; then
+        python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
+                                                --scenario "${DATADIR}"/habitat/pasture.tif \
+                                                --area "${DATADIR}"/area-per-pixel.tif \
+                                                --scale "${PIXEL_SCALE}" \
+                                                --output "${DATADIR}"/habitat/pasture_diff_area.tif
+    fi
+fi
 
 # Generate the restore map
-python3 ./prepare_layers/make_restore_agriculture_map.py --pnv "${DATADIR}"/habitat/pnv_raw.tif \
-                                                        --current "${DATADIR}"/habitat/current_raw.tif \
-                                                        --crosswalk "${DATADIR}"/crosswalk.csv \
-                                                        --output "${DATADIR}"/habitat/restore_agriculture.tif
-
-aoh-habitat-process --habitat "${DATADIR}"/habitat/restore_agriculture.tif \
-                    --scale 0.016666666666667 \
-                    --output "${DATADIR}"/habitat_maps/restore_agriculture/
+if check_scenario "restore"; then
+    if [ ! -f "${DATADIR}"/habitat/restore.tif ]; then
+        python3 ./prepare_layers/make_restore_map.py --pnv "${DATADIR}"/habitat/pnv_raw.tif \
+                                        --current "${DATADIR}"/habitat/current_raw.tif \
+                                        --crosswalk "${DATADIR}"/crosswalk.csv \
+                                        --output "${DATADIR}"/habitat/restore.tif
+    fi
+
+    if [ ! -d "${DATADIR}"/habitat_maps/restore ]; then
+        aoh-habitat-process --habitat "${DATADIR}"/habitat/restore.tif \
+                            --scale "${PIXEL_SCALE}" \
+                            --output "${DATADIR}"/habitat_maps/restore/
+    fi
+
+    if [ ! -f "${DATADIR}"/habitat/restore_diff_area.tif ]; then
+        python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
+                                                --scenario "${DATADIR}"/habitat/restore.tif \
+                                                --area "${DATADIR}"/area-per-pixel.tif \
+                                                --scale "${PIXEL_SCALE}" \
+                                                --output "${DATADIR}"/habitat/restore_diff_area.tif
+    fi
+fi
 
-python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
-                                        --scenario "${DATADIR}"/habitat/restore_agriculture.tif \
-                                        --area "${DATADIR}"/area-per-pixel.tif \
-                                        --scale 0.016666666666667 \
-                                        --output "${DATADIR}"/habitat/restore_agriculture_diff_area.tif
+# Generate the restore_agriculture map
+if check_scenario "restore_agriculture"; then
+    if [ ! -f "${DATADIR}"/habitat/restore_agriculture.tif ]; then
+        python3 ./prepare_layers/make_restore_agriculture_map.py --pnv "${DATADIR}"/habitat/pnv_raw.tif \
+                                                                --current "${DATADIR}"/habitat/current_raw.tif \
+                                                                --crosswalk "${DATADIR}"/crosswalk.csv \
+                                                                --output "${DATADIR}"/habitat/restore_agriculture.tif
+    fi
+
+    if [ ! -d "${DATADIR}"/habitat_maps/restore_agriculture ]; then
+        aoh-habitat-process --habitat "${DATADIR}"/habitat/restore_agriculture.tif \
+                            --scale "${PIXEL_SCALE}" \
+                            --output "${DATADIR}"/habitat_maps/restore_agriculture/
+    fi
+
+    if [ ! -f "${DATADIR}"/habitat/restore_agriculture_diff_area.tif ]; then
+        python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
+                                                --scenario "${DATADIR}"/habitat/restore_agriculture.tif \
+                                                --area "${DATADIR}"/area-per-pixel.tif \
+                                                --scale "${PIXEL_SCALE}" \
+                                                --output "${DATADIR}"/habitat/restore_agriculture_diff_area.tif
+    fi
+fi
 
 # Generate the restore all map
-python3 ./prepare_layers/make_restore_all_map.py --pnv "${DATADIR}"/habitat/pnv_raw.tif \
-                                 --current "${DATADIR}"/habitat/current_raw.tif \
-                                 --crosswalk "${DATADIR}"/crosswalk.csv \
-                                 --output "${DATADIR}"/habitat/restore_all.tif
-
-aoh-habitat-process --habitat "${DATADIR}"/habitat/restore_all.tif \
-                    --scale 0.016666666666667 \
-                    --output "${DATADIR}"/habitat_maps/restore_all/
-
-python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
-                                        --scenario "${DATADIR}"/habitat/restore_all.tif \
-                                        --area "${DATADIR}"/area-per-pixel.tif \
-                                        --scale 0.016666666666667 \
-                                        --output "${DATADIR}"/habitat/restore_all_diff_area.tif
+if check_scenario "restore_all"; then
+    if [ ! -f "${DATADIR}"/habitat/restore_all.tif ]; then
+        python3 ./prepare_layers/make_restore_all_map.py --pnv "${DATADIR}"/habitat/pnv_raw.tif \
+                                        --current "${DATADIR}"/habitat/current_raw.tif \
+                                        --crosswalk "${DATADIR}"/crosswalk.csv \
+                                        --output "${DATADIR}"/habitat/restore_all.tif
+    fi
+
+    if [ ! -d "${DATADIR}"/habitat_maps/restore_all ]; then
+        aoh-habitat-process --habitat "${DATADIR}"/habitat/restore_all.tif \
+                            --scale "${PIXEL_SCALE}" \
+                            --output "${DATADIR}"/habitat_maps/restore_all/
+    fi
+
+    if [ ! -f "${DATADIR}"/habitat/restore_all_diff_area.tif ]; then
+        python3 ./prepare_layers/make_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
+                                                --scenario "${DATADIR}"/habitat/restore_all.tif \
+                                                --area "${DATADIR}"/area-per-pixel.tif \
+                                                --scale "${PIXEL_SCALE}" \
+                                                --output "${DATADIR}"/habitat/restore_all_diff_area.tif
+    fi
+fi
 
 # Generate urban all map
-python3 ./prepare_layers/make_constant_habitat.py --examplar "${DATADIR}"/habitat_maps/arable/lcc_1401.tif \
-                                                   --habitat_code 14.5 \
-                                                   --crosswalk "${DATADIR}"/crosswalk.csv \
-                                                   --output "${DATADIR}"/habitat_maps/urban
-
-python3 ./prepare_layers/make_constant_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
-                                                   --habitat_code 14.5 \
-                                                   --crosswalk "${DATADIR}"/crosswalk.csv \
-                                                   --area "${DATADIR}"/area-per-pixel.tif \
-                                                   --scale 0.016666666666667 \
-                                                   --output "${DATADIR}"/habitat/urban_diff_area.tif
+if check_scenario "urban"; then
+    if [ ! -d "${DATADIR}"/habitat_maps/urban ]; then
+        python3 ./prepare_layers/make_constant_habitat.py --examplar "${DATADIR}"/habitat_maps/arable/lcc_1401.tif \
+                                                        --habitat_code 14.5 \
+                                                        --crosswalk "${DATADIR}"/crosswalk.csv \
+                                                        --output "${DATADIR}"/habitat_maps/urban
+    fi
+
+    if [ ! -f "${DATADIR}"/habitat/urban_diff_area.tif ]; then
+        python3 ./prepare_layers/make_constant_diff_map.py --current "${DATADIR}"/habitat/current_raw.tif \
+                                                        --habitat_code 14.5 \
+                                                        --crosswalk "${DATADIR}"/crosswalk.csv \
+                                                        --area "${DATADIR}"/area-per-pixel.tif \
+                                                        --scale "${PIXEL_SCALE}" \
+                                                        --output "${DATADIR}"/habitat/urban_diff_area.tif
+    fi
+fi
 
 # Fetch and prepare the elevation layers
-reclaimer zenodo --zenodo_id 5719984  --filename dem-100m-esri54017.tif --output "${DATADIR}"/elevation.tif
-gdalwarp -t_srs EPSG:4326 -tr 0.016666666666667 -0.016666666666667 -r max -co COMPRESS=LZW -wo NUM_THREADS=40 "${DATADIR}"/elevation.tif "${DATADIR}"/elevation-max.tif
-gdalwarp -t_srs EPSG:4326 -tr 0.016666666666667 -0.016666666666667 -r min -co COMPRESS=LZW -wo NUM_THREADS=40 "${DATADIR}"/elevation.tif "${DATADIR}"/elevation-min.tif
+if [ ! -f "${DATADIR}"/elevation.tif ]; then
+    reclaimer zenodo --zenodo_id 5719984  --filename dem-100m-esri54017.tif --output "${DATADIR}"/elevation.tif
+fi
+if [ ! -f "${DATADIR}"/elevation-max.tif ]; then
+    gdalwarp -t_srs EPSG:4326 -tr "${PIXEL_SCALE}" -"${PIXEL_SCALE}" -r max -co COMPRESS=LZW -wo NUM_THREADS=40 "${DATADIR}"/elevation.tif "${DATADIR}"/elevation-max.tif
+fi
+if [ ! -f "${DATADIR}"/elevation-min.tif ]; then
+    gdalwarp -t_srs EPSG:4326 -tr "${PIXEL_SCALE}" -"${PIXEL_SCALE}" -r min -co COMPRESS=LZW -wo NUM_THREADS=40 "${DATADIR}"/elevation.tif "${DATADIR}"/elevation-min.tif
+fi
 
 # Get species data per taxa from IUCN data
 for TAXA in "${TAXAS[@]}"
 do
-    python3 ./prepare_species/extract_species_psql.py --class "${TAXA}" --output "${DATADIR}"/species-info/"${TAXA}"/ --projection "EPSG:4326"
+    if [ -f "${DATADIR}"/overrides.csv ]; then
+        python3 ./prepare_species/extract_species_psql.py --class "${TAXA}" \
+                                                        --output "${DATADIR}"/species-info/"${TAXA}"/ \
+                                                        --projection "EPSG:4326" \
+                                                        --overrides "${DATADIR}"/overrides.csv
+    else
+        python3 ./prepare_species/extract_species_psql.py --class "${TAXA}" \
+                                                        --output "${DATADIR}"/species-info/"${TAXA}"/ \
+                                                        --projection "EPSG:4326"
+    fi
 done
 
 # Generate the batch job input CSVs
@@ -176,7 +264,7 @@ python3 ./utils/persistencegenerator.py --datadir "${DATADIR}" \
                                         --scenarios "${SCENARIOS[@]}"
 
 # Calculate all the AoHs
-littlejohn -j "${SLURM_JOB_CPUS_PER_NODE}" -o "${DATADIR}"/aohbatch.log -c "${DATADIR}"/aohbatch.csv aoh-calc -- --force-habitat
+littlejohn -j "${SLURM_JOB_CPUS_PER_NODE}" -o "${DATADIR}"/aohbatch.log -c "${DATADIR}"/aohbatch.csv "${VIRTUAL_ENV}"/bin/aoh-calc -- --force-habitat
 
 # Generate validation summaries
 aoh-collate-data --aoh_results "${DATADIR}"/aohs/current/ --output "${DATADIR}"/aohs/current.csv