Interesting - thanks for writing all of that out, Meya. Good information.
It's not uncommon for a cat to just be bouncy, no matter what the dose is - if their body has "forgotten" normal numbers, they react by bouncing. I'm thinking of JD, who made it to 20, and was diabetic for 9 years, I believe. He basically bounced every single day.
Erin, great job getting those pm cycle tests in. It helps. When I see a green number, like that 48, I look to see when it clears - should be in about 3 days or less. Three days would've been today's day cycle. I'd just make a habit of trying to catch how low he goes when he clears the bounce, so you know about dosing. Usually with a 48 you would reduce his dose to 0.25u.
How does he seem other than his blood sugar? Does he have his "5 P's?" Purring, playing, preening, pooping & peeing? Everything working ok?