Ah, yes. I think you're right about the carbs. Eating carbs is one of the most common causes of bouncing numbers for our kitties. Even just a couple pieces of kibble or a nibble of higher carb food can send our kitties soaring or diving for a few cycles afterwards. The easiest thing to do is to transition all of your kitties onto low carb food if you can. If that isn't possible, then eating in different rooms with closed doors, and then picking up any leftovers and putting them away. Carbs are kryptonite for our kitties around here. Some kitties do okay up to 10%, most seem to do better closer to 5%.
Also, I might be reading it wrong, but it sounds like your test/dosing time isn't quite 12 hours. Is that right? If so, is there any way you can get it to be a 12-hour schedule? (and I apologize if you've already talked through this with folks and your schedule just doesn't allow it - please know I understand how complicated scheduling can be and am not just trying to be bossy
) As the prozinc wears off toward the end of the cycle, numbers can rise quite quickly. Which means a pre-shot test after 12 hours can seem really really high, while one a bit early can be surprisingly low. If there's no way to be on a 12 hour cycle, just being as consistent as you can with whatever schedule you have will help, and then making sure when folks are offering advice that they know you're not on a standard schedule so they can factor that in.
I'll probably be around starting at about 7:30 your time, and Kris and Rachel are up before then, so hopefully if you need anything someone will be around in the morning.
). Honestly, since it's out of the normal pattern, it could be anything or a combo of things...but there's no way to know for sure, and unless it becomes more normal, I'd treat it as a one off. 