Well you gotta like that AMPS better, but it still doesn't all add up to me, darn it! Doesn't look anywhere close to low overnight, hard to imagine that the extra 0.2 would actually be putting him too low. Well, my best thought is just to continue to gather data. Wish I had more insight, but it looks to me like a puzzle that will only come together either with sheer dumb luck, or with figuring out more & more pieces over time until you find you can explain & predict what is going on. It helps that he is so consistent in some ways, but then in other ways he doesn't get a consistent response, so that makes it tough.
I hope he is feeling well. That is what matters most!!!