Laura
Have you tested her for ketones?
You've done a good job of getting more tests since the p.m. cycle of 6/22 and I don't see anywhere in there that she could have had time to go low and come back up. I'm worried that she could be having some dental issues and if she has an infection and she's not eating and the insulin is not enough, she could be at risk for developing ketones and if they do develop, then DKA.
My suggestions would be:
--test for ketones at least every single day; if you can catch her twice a day, I'd do it as long as her numbers are this high,
--get her in to see a vet to look at her mouth, check her temp, etc. and see if there is any potential infection going on; unfortunately, if there is a stray root that was left behind that has become infected, the vet might not be able to tell without digital dental X-rays which require anesthesia
--raise her dose of insulin but keep testing as much as you have been; she's been low enough on this dose to have earned a reduction (although it wasn't taken); but there is something else going on now that concerns me. These aren't bounce numbers at this point. I'd raise her dose to 2.5u as long as you can keep testing a few times during each cycle; we don't want her crashing down on you but her nadirs are pretty high right now.