PAC Accounting Entries Has Reversal Period When They Are Transferred to GL

We are using PAC cost method. Our Periodic Inventory accounting entries have value of Reversal Period when they were transferred to GL interface table. The value of Reversal Period is defaut to next period. So when we run the request that transfers accounting entries to GL, there's a warning. Through the request ouput, we can see the status for the entries is ER02, which means the reversal period is not in a open period.

The question is:

1.    Why will there be value of Reversal Period for PAC entries?

2.    Where can I control the default value for the reversal period?

 

It will be apprecaited if you guys can share with us your ideas.