I have setup mobfarm with drawers and void upgrades in already fully upgraded drawers.
So in this particular case I have put void upgrade on drawer (can be seen in first image, upper left corner) with gunpowder and solidified experience, I'm using @Translocators to push items into drawer controller, which I already tried to break and replace (the same goes for @Translocators...) and I also emptied and replaced old 2x2 drawer with new 2x2 drawer (separately made block) (in case drawers store some metadata (NBT?) that is not reset when adding void ugrade).

I also thought that problem might still be on the side of @Translocators, but I'm leaning to problem with drawers, because drawer is not full right now (I could take out 1 emerald upgrade).

It seems like this is a problem with @Translocators combined with drawers with void upgrade...

Probably inserting into drawer controller via external input (not player based) makes the external input see the drawer controller as the correct drawer for inputting..?

Also I'm not sure if drawers should share it's upgrades via any programming interface... I mean yeah, capacity (unlimited for void upgrade?) sure, current amount - sure, but for controlling if drawer is full or not, we have redstone upgrades..

((That's based mainly on my speculation & knowledge about programming tho :/))