Hi,
If I understand your requirement correctly you can resolve the proces sending the unpacked pallet into PI area using DIFW exception code. But perhaps you will need to create a new picking task at once.
In theory, you can try to copy BIDF into a new one and modify the configuration so it sends the difference into PI area. This exception code should create a new picking task with the same SRCI rules. While having the actual pallet in the PI area, another one should come up.
From PI area back to pickface should be a manual PI proces.
Petr