Anyone experiencing TSH levels rising with PV and on HU?

I have hypothyroidism and been on levothyroxine for years and stable levels of TSH. Just diagnosed with polycythemia in February 2026 and started on hydroxyurea, taking two 500 tablets daily. By May my hematocrit and platelet counts decreased to hit my target. My oncologist decreased my HU to one tablet MWF, with two the remaining days.
Meanwhile, I had my annual physical with my primary. Had my annual TSH run and it was elevated. Both oncologist and primary just shrugged when I asked if PV affected my TSH. Primary upped my levothyroxine dosage and have a repeat level in 8 weeks.
Well, had my repeat test today and my TSH went up again! Despite decreasing my HU and increasing my levothyroxine. Waiting to hear what my primary says.
Anyone with PV experienced TSH levels rising?
I take my levothyroxine in the morning on an empty stomach and the HU in the evening after dinner.