delimiter + tipdate doesn't work as expected

[rmcclosk]

Run kamphir with this command.

python /home/rmcclosk/Documents/kamphir/kamphir.py -delimiter '_' -datefield 1 \
        -ncores 6 -nthreads 6 -nreps 6 -tscale 0.00273791 SI src/settings.SI.json data/01_prune/bc-subtypeB.timetree.nwk results/SI.log

Many errors like this:

Warning: Failed to parse tipdate from label FD8D35C1_2123
Warning: Failed to parse tipdate from label 742916E6_4147