Experience with Tufts Medicare Insurance and Xyrem/Xywav

I am turning 65 soon and will have to change insurance plans when I go on Medicare. I have been on Xyrem for a few years now.

I live in Boston and there are a handful of plans that might be a good fit for me. One of those is Tufts Medicare Preferred HMO Prime Rx (HMO). They just released their formulary for 2022 and it shows there is no pre-authorization required for Xyrem or Xywav. I called them to confirm and they confirm there is no preauth required. Does anyone here have Tufts Medicare insurance and can you confirm that there aren't any issues getting Tufts to pay for Xyrem? I realize the cost is going to be very high as it is a Tier 5 drug but the MA Prescription Advantage program will pay for part of the cost. If you live in Boston and have had an experience with some other insurance company and Xyrem/Xywav, I would appreciate hearing about your experiences good or bad. Thanks in advance.