Well, you have probably already shot by now, but I can still give my thinking....
Yesterday, the 3u gave him a high flat cycle. Last night the 2u gave you some curve and some pinks, but still rather flat.
Today, the 3u gave you that same ugly high flat cycle until +9 when he fell 200 points (I think HI means 600+), then he came up a bit, but ended lower than he started this morning.
I know you want low numbers, at least pinks. The problem is, there isn't enough data yet to determine whether to go up or go down. We all know he was the lowest when he went without insulin for a day or so. But then the whole UTI/ketone problem showed up.
Someone pointed out that yes, he did have ketones, but he didn't go as far as "DKA". I originally feared that the removal of insulin caused the ketones, but I don't really think that is what happened. I think the UTI was lurking since you were dosing 8u, and just manifested itself coincidentally when you dropped the dose.
High numbers mean a higher risk of ketones, but you are checking for them religiously. (I have to say, Martha, that of all the "newbies" I've seen in the past 3 months, nobody has done a better job of testing!).
My gut says the dose needs to be lower, or kept at 2.0 for several cycles.
There has to be something that is constant. The diet is wonky, and undergoing change. His numbers are all over the place, but it's only 2 days of numbers. It's just that he hasn't been able to "settle" into anything, because things are so different day-to-day.
In your shoes, Martha, I'd be going bonkers. All you want is a happy healthy kitty that you don't have to stress out over every two hours! You don't want to hear (I assume) that "patience" is needed.
I guess I feel that unless you keep one thing constant, this puzzle will never get solved. I think the dosage is the easiest variable to keep constant.
Carl