Hi & welcome!!!!
One thing you can try is feeding multiple small meals (if you aren't doing that already) rather than 2 bigger meals. A lot of people around here let their kitties free feed, or feed maybe 4 smaller meals, or a bunch of smaller snacks, or whatever works for their schedule. If their pancreas is working (and it sounds like Motor's is), eating will trigger it to produce insulin, so if you get a number that is higher than you like you can feed a little bit, and then test in a couple hours and see if they have brought themselves down to a better number.
I might consider 180 as your point to give a micro dose, or 200 for a bigger dose (I don't recall what his dose was when he was getting regular shots? I would add all that back data to your spreadsheet - even if it's tests from the vets, then just put that in the notes, and you could put a date range where you were giving x units even if you were shooting blind - don't necessarily need to give each day its own line if there's no data, but maybe just put a note in one line "shot 1u (or whatever) BID from x to x dates", something like that).
If he continues to steadily creep up I agree you might not want to wait til 180, but I'd post again if you get to a point where you are thinking a shot is in order and see what people say. I would experiment with feeding small portions first. It's tricky at this point - you don't want to withhold insulin if they need it, but you don't want to give it on a non-diabetic number either, so it's hard to know what to do. Sometimes when they are going OTJ they run in the low blues for a couple days, then drop themselves to greens on their own, so I'd wait a little longer and see what happens, if he keeps creeping up, or if his pancreas takes over on its own.
