If you accidentally move, add, update, or delete an allocation from the Schedule, you can undo the last action using Ctrl-Z (PC) or Command-Z (Mac). Undo is not supported for replacement actions.

Unfortunately, due to our privacy and security agreements, we aren’t able to recover deleted information on an account. We can only restore information lost due to a system-wide issue. To avoid losing historical data, we always recommend archiving people and projects instead of deleting them. 
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