FTE Validation for replacement hiring

Summary:

Content (required):

We have a validation that you cannot hire more persons into a position than the FTE/headcount of the position. We want to fill up the position for a staff in transition to exit the company, but the system not allow due to the FTE not enough. It's the replacement hiring in this case, how can the system smart enough to free up the FTE for the resigned staff's position to be filled? We don't want to increase the FTE temporary in manual way, no warning message or error prompted in this case.

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