Hi,
I'm no expert on IAA kitties and Gussie was a Lantus kitty, but in general, the way I liked to think of it that helped me was this:
The cats body gets used to being in high numbers, it's comfy there. Then when we start adjusting the level using a hormone, i.e. Insulin, the numbers start to lower. Then the liver notices and freaks out and says danger danger, must get back to that high comfy level we're used to!! So it dumps a lot of counter hormones and that causes the trampoline bounce back to higher numbers. With time the liver get used to more normal numbers and will barely look up and say huh?Oh I recognize this..and won't dump those counter hormones and the numbers will flatten out.its a pretty simplified version but that's how I wrapped my head around the process..
Hope it makes some kind of sense...
BUT I'm going to bump you up because as mentioned I'm no expert and out of my knowledge base on this one!

Going to also tag some more experienced folks who I've seen help
@Wendy&Neko ,
@Doodles & Karen