Longtime chronic headaches are more frequent since starting CPAP: advice?

Hi - I'm F60, overall fairly healthy and normal weight (5'4" and 133 lb), work out lifting weights, hiking, biking, etc. ~5 days a week, healthy diet, rarely consume alcohol (once every month or two at most), moderate caffeine before lunch. My heart rate and BP are on the low end of normal, though I do have moderately high cholesterol.

I've dealt with headaches since age 18, much more frequent in the past 25 years. Ubrelvy is my current rescue med and is usually effective, but prescription instructions are to take it no more than 8 days per month. Ibuprofen is pretty effective for headaches but my PCP instructed me to avoid NSAIDs after some slightly abnormal kidney numbers on routine tests a few years ago. Tylenol is generally not helpful for treating my headaches. Headaches often last for a full day or longer. I go about life as usual but usually have to back off or skip my workout when I'm in a lot of pain.

During an unrelated elective surgery last winter, I apparently experienced apnea events, which got me sent for a sleep study, the result of which was Mild obstructive sleep apnea (AASM AHI 5.4/hr; CMS AHI 1.6/hr). Lowest ox sat during that time was 88%. After consulting with my headache provider, I decided to give CPAP a try in hopes it would reduce my headache frequency or duration. I opted for the AirFit N20 - the PAP clinic recommended it since silicone irritates my skin. During my week 1 check-in they had me reduce the hose temperature to cut down on rainout, and told me to sleep with the hose under the covers. It helped a little with condensation. However, I've had an all-day headache over 50% of the days I've used it beginning 12/24. I also have worse evening sleepiness than I had before starting CPAP, and it's harder to concentrate on work.

I haven't started downloading data and working with Oscar yet, but my Apple watch shows I'm waking up 6+ times a night (usually to adjust the mask and/or dry it but occasionally to just remove it altogether).

I do have a tendency to clench my jaw when I'm asleep, and the headaches are actually more intense if I use my mouth guard, so I've stopped that. I can't take Ubrelvy every day. What am I not doing that I could be doing to improve my tolerance for this? It is hard to feel the benefits when I'm so tired and in constant pain. I'd welcome suggestions, especially from other headache heroes. Thanks!