Changing assembly

I have an assembly with a pallet and a child step with 10 boxes (the same) on top of the pallet. The pallet is then depalletized. After other processes the pallet then needs to be palletized again, with the same boxes. Now, one of the boxes is rejected and needs to be put aside and the pallet leaves with 9 boxes.
I have solved this by creating another assembly with a pallet only holding 9 boxes. I then do an assembly swap while it is just an empty pallet and therefore the swap is not visible. Is there a more correct way to do this?

If convenient, you can share the layout so you can get better help. :melting_face: