First run on Muria and spotting unusal behaviour on the labs, I imported enough optimisation cards to run the offworld chlorine compounds research but noticed the acid packs were draining faster, quick test with 100 of each left 18 optimisations leading me to believe the lab productivity bonus (18%) is not being applied to the acid packs, is this intended?

Science packs that spoil will only give off a percentage of their fullness based on the spoilage percentage. Due to the high spoilage rate of acidworking science this will usually lead to packs being consumed while almost spoiled, hence giving off less bonus.
It's why the pack only spoils once activated and why the base recipe makes 5 packs per cycle.