Oh Peggy thank you so much for the update. I am so pleased to hear Oliver is doing well. I have to admit, I have been sitting here holding my breath wondering!
I assume your son works in a human lab so that obviously gives him a good base of knowledge about human glucose but the composition of human and cat blood is not the same. The cat's glucose is largely carried in the plasma of the blood whereas with a human most of the glucose is in the red blood cells. That's why there is a different meter for our pets. The value the AT meter gives you is closer to a lab result from a lab calibrated for animal blood.
So in reality the Relion meter is not more accurate. Both meters are right...they are just calibrated to read different types of blood, thus the different readings and all you have to do is follow the reference ranges for the type of meter you are using. If you are going to use the numbers from the Relion going forward, then the protocols here provide reference numbers for you to use with a human meter to make decisions about dosing Oliver.
Once you get more mid cycle tests, you will be able to give Oliver some insulin at lower readings if needed and there are a lot of hands on "experts" here to guide you should you have questions about what dose to give because believe it or not, missing doses isn't always the best answer either. This morning however, it was the right call!
Did you have to steer Oliver's BG with food/karo last night to keep him in the 70's? That 98 this morning could be a bit of a bounce from going even lower last night after your +6 reading of 74. If he did go lower, he may be more sensitive to the insulin now too.
I would suggest you get a couple of tests in mid cycle today if you can, to see where he goes without insulin on board. Tonight, I'd suggest you post in the Lantus/Levemir section if you are unsure what to do and someone can give you advice on whether to shoot or not and if so, what dose would be safe. I'm thinking his numbers may be up today so please don't panic if they are.This is a normal reaction after going to low numbers his body is no longer accustomed to.
Are you using syringes to inject Oliver or the insulin pen? You have to use syringes to be able to give .25 or .50 doses for instance and quite often those low doses are needed to keep a cat safe but keep their numbers at a low enough level to rest the pancreas and hopefully promote remission.
I know all this get very complicated. The important thing is that Oliver is OK. I'm sure you are a bit blurry eyed! But you gained a lot of experience last night!