I have been upgrading my storage and silo buildings to be able to cover that Cocina boost. Finally, they're almost enough to stash required in-game resources to buy a level 5 Cocina. I just need another 24-36 hours.
For the reference, a level5 Cocina upgrade requires 129k drugs, 270k weapons, 324k alcohols. At these levels, if you want to use the in-game resources, it is kinda boring since you need to wait a lot for a single drug production upgrade.
I hope the battle system will be back soon.