@HighHopes I created a new topic for your question. The answer is in the Medicare Infusion Pump LCD (Local Coverage Determination). As of May 2025 it says:
Continued coverage of an external insulin pump and supplies requires that the beneficiary be seen and evaluated by the treating practitioner at least every 3 months.
I suggest bookmarking this page and checking it once a year for updates as long as you have Part B and a pump covered by it. The document gets updated often and personally I had to read it more than few times to really understand it.