Okay first off he's not OTJ. Not sure if you meant to put up that icon or not. But just in case, OTJ stands for Off The Juice or in remission and no longer receiving insulin. For that to happen the cat has to be able to keep their BGs between 40-120 for 14 days on diet alone.
Since Kitty Boo is still on insulin just finally in lower numbers you keep everything the same. Unless you get a reading lower than 50 in which case he has earned himself a dose reduction of a quarter unit (.25)
Mel and The Fur Gang