Oracle EBS LCM with PMAC in OPM Inventory Costing

In the case of an item, X, received in the September period:
1st of September: Item is received with estimated charges.
15th of September: Item is issued from the store.
29th of September: Item's AP invoice for the actual amount is entered, and the actual cost is calculated.
Q1: What is the expected behavior for the items issued before the actual cost is calculated? Will the cost be re-calculated for this item since it is within the same period?
Q2: If the actual AP invoice is entered in October, will the system hit the LCM variance with the actual amount related to the issued quantity? Or will it distribute this amount to the non-issued items related to this shipment?