Run AM Calc with "Generate Absence Payable Time" turn on

When running AM Calc with "Generate Absence Payable Time" turned on, the absence transactions send over to TL Payable Time after the process.  For some reasons, the process also set TL time reporter ECD back in time.  In our case, to time prior to cutover date (we do have historical time entries converted from our PS 9.1 environment).

Question: How can we stop AM flipping the ECD back to an old time period and then invoking the GENPT which abends on an old rule or related rule map or related time calendar?