First of all, I'd skip the appointment with the IM vet. That seems like a lot of fuss and bother and expense for a dosing suggestion for two weeks in the future when we can help you now. Especially if he has no knowledge or interest in considering IAA. I'm not sure what value he can provide.
Thank you, Wendy, for such a detailed and helpful response. I do agree with you about the IM vet, firstly. I thought actually of keeping the appointment but not bringing Eddie. I more or less need this IM; he's the only game in town, in the entire BC Interior in fact, and so have to keep some relationship with him, if only for prescriptions, that is, when he's willing to write them and not turn them over to the regular vet. It's a dance.
First of all Jodie, you need to follow Eddie's lead. Think like a cat and relax, live for the day.
Don't obsess over one day's or one cycles numbers. Follow the TR protocol. This dose got him down to 119, which is a pretty good number. TR says to hold doses with blues for 6-10 cycles, I would hold longer than 6 because of that 119. He's just bouncing now. Let's see where he goes when he breaks the bounce. He might be headed there today, that's a pretty good drop to +3.
I guess I'll be holding the dose as a +6 put us back in the blue zone. He looks really good today, in fact, has followed what you thought might happen after +3.
I think the radiation oncologist is correct about the tumour but you are interpreting what she said incorrectly. SRT neuters the tumour cells. That means they are still active until they die off. That is a slow process that can take 2-3 years. The radiation oncologist said there is no tumour regrowth and that it's smaller - that is a good sign, some of the tumour is gone. But you still have to deal with some tumour effects until all the cells have died off.
Yes, I do trust the radiation oncologist. I do read her loud and clear regarding her interpretation but was getting snagged on the DM/IAA issue because, you're right, Eddie is dealing with more than acromegaly but it is challenging to separate the DM/IAA from that dread condition and its effects. The affects are mine. 
It isn't all about acromegaly, there is some regular DM stuff in there too. Eddie is also dealing with both glucose toxicity and antibodies. If Neko didn't see green in over 5 days, she started developing glucose toxicity. It was 14 days from Eddie's last greens to that 119 which is in the normal blood sugar range for the AT.
That 119 was a beautiful thing.
As an aside, the threat of glucose toxicity was one of the reasons I wanted you to increase faster back to his last good dose. But what's done is done. Less is known about the antibodies, but they seem to take the opportunities of higher numbers to really grab hold.
I'll say. And, it's hard dealing with an IM who thinks IAA is fantasy material.
You have to "show them the green". Have you ever looked at
Oberon's spreadsheet. He is just deal with IAA which makes the antibody effect clearer. His IAA number was 83, so not far off.
I will definitely look there.
Your question is "how to regulate Eddie?". My answer is follow the protocol and put on your patience pants. SRT cat are often very bouncy. Have you looked at
Max's spreadsheet or Neko's after her first SRT? There isn't a lot you can do about this but get to a safe dose where he sees lots of normal numbers. The rest is up to Eddie. Seriously, you have to learn patience and to sit on your hands. I know how difficult this is cause I felt it too. Take up exercise, yoga, whatever, but don't stress over something you have little control over.
It's a good thing that I do actually exercise! Can you imagine if I didn't.
To combat the glucose toxicity, you have to safely get him to a dose where he sees more normal numbers and starts to earn reductions. Emphasis on "safely". You still have the possible SRT impact that can happen any time. We can't predict when the next set of tumour cells will die. Don't rush increases, wait to see where he goes when the bounce is over. If he doesn't see high greens at that point, then increase to 9.5 units.
Here the point is for me to learn when to determine if a bounce is over or not. That's why I was leaning into the 6th cycle to ask about the increase; but I think, given his +6 today, holding is appropriate, for now.
The research from England with a very large scale study showed about 26% of cats had acromegaly. An also good sized study in Netherlands and Switzerland showed 18% had acromegaly, but I'm not as familiar with the details of how they chose the cohort with that one.
but you're so welcome LOL