I started at every 3-4 months after initial diagnosis. I’ve since been moved to every 6 months since blood counts have been stable.

I depends on where you are in treatment. Initially, once per month would be reasonable until your baseline is clearly established. If you remain asymptomatic, at some point the CBCs will be less frequent. Your doc will also likely periodically do a CMP, check iron levels, and perhaps a few other things like an iron panel, LDH, Prothrombin Times, etc. I would expect that at some point you would be doing CBCs every third month.

Note this would change if you initiate cytoreductive medications. Then you would likely do CBCs about every two weeks until you reach stability. CMPs would also be done more often.

I have always been 6monthly once diagnosed. 7 years now. I am same as you. CALR type 1.
The usual tests are:
CBC
Us & Es
Liver profile
LDH
I think that's all.

I do labs monthly. My oncologist has placed me on “cruise control,” meaning my numbers (373) are so good I only see him every four months now💕

Yep, depends on whether your labs are stable, or not.

I went thru months last year of first weekly and then every two weeks, with three phlebotomies in there.

Things settled down, and I have been on monthly labs the last 8 months or so.

The labs are how our docs know our meds are working, I remind myself. ☺️