Push, pull and merge?

[NorbNorb]

If I have three devices A, B and C, all working on their own local stores first (iCloud disabled).
How can I

• Push:
  Device A enables cloud and uses its local store to overwrite any data in iCloud and other devices can pull from there.
• Pull:
  Device B enables cloud and deletes its local cloud store for rebuilding it from iCloud.
• Merge:
  Device C enables cloud and keeps its local data, but merges incoming transaction logs.

My implementations so far are:

• Push:

[[[AppDelegate sharedAppDelegate] ubiquityStoreManager] deleteCloudContainerLocalOnly:NO];
[[[AppDelegate sharedAppDelegate] ubiquityStoreManager] setCloudEnabled:YES];

• Pull:

[[[AppDelegate sharedAppDelegate] ubiquityStoreManager] deleteCloudContainerLocalOnly:YES];
[[[AppDelegate sharedAppDelegate] ubiquityStoreManager] deleteLocalStore];
[[[AppDelegate sharedAppDelegate] ubiquityStoreManager] setCloudEnabled:YES];

• Merge:

[[[AppDelegate sharedAppDelegate] ubiquityStoreManager] deleteCloudContainerLocalOnly:YES];
[[[AppDelegate sharedAppDelegate] ubiquityStoreManager] setCloudEnabled:YES];

Our observations are that a push of device A followed by a pull of device B work if iCloud wasn't populated before. Devices will be in sync then. But if the devices disable iCloud again and make another push & pull procedure, all pulling devices don't show any data.

We can get the devices back in sync if we do a
objective-c[[[AppDelegate sharedAppDelegate] ubiquityStoreManager] deleteCloudContainerLocalOnly:NO]; wait for a short time and then hit the the push and pull buttons on the devices again.