How do folks handle mid-period new hires?

I work for a large employer (50,000+ EEs) who processes absences using monthly periods. We have pretty regular turnover, so there's always new employees coming in the middle of the processing periods. We're also a heavily union shop with some entitlements contractually available immediately upon hire. As such, there's a need to re-run the identify step to make 100% certain that we're picking up all new hires.

We're looking in to scheduling the process, but haven't had much luck since we need to cancel in order to re-identify, and the run control gets wiped any time a cancel step is run.

Is anyone else in this situation? How do you handle mid-period hires?