Glad you finally added syrup. He needs to stay UP!
Today was a bounce breaking cycle, 382 last night sliding down to 167 this AM. Not the best time for an increase, as there is already downward momentum from the bounce break. Adding an increase gives it extra momentum you don't need. And can result in reductions that aren't really representative of what the dose could do. Having said that, I would reduce. As you said, it was quite dramatic. Your choice if you want to go back to 16 or split the difference to 16.5.
Acros don't have breakthrough doses. It's not about pancreatic healing, but rather matching insulin to changing GH output. What acros do have is the correct dose at a particular point in time.