Considered making one into a headband + chinstrap for your cpap users who already use a chin strap?

Then we can replace the chin strap part regularly as it wears out.

I’ve seen a few people on the cpap forum that wear the full ecg skull cap for data recording.

I think you mean EEG, not ECG.

Our first product won't be focused on CPAP users, but we're based in Sydney, Australia, which is the home of ResMed, so have a few contacts there. It's not an area we'd look at going into on our own.