Absence accruals crediting entire tenure vs full time service only

Summary:

We recently had a situation where 2 employees who went from part time assignments to full time assignments were accruing PTO at a rate that reflected their entire tenure vs their full time service. The enrollment dates on the leave banks are commensurate with their full time assignment start dates, and the leave anniversary dates were never updated to credit them with their entire tenure.

We haven't seen it with others and have corrected the issue, but I am wondering how/why this would happen so that we can check for it in the future.

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