Newbie -- CPAP maintenance, hoses and tricare insurance

[updownmostly]

I have a resmed S7 I guess I've had it for about 4 years maybe longer. I tried using the full mask but then gave it up. I couldn't use it now since I've got a beard. So I got the nasal pillow set, fits up in my nose, I'm much happier with that since I sleep on my side quite a bit. Couple questions:

How often should these things be calibrated?

My hoses are falling apart and my mask has lost a lot of the padding on top. I have a lot of sports tape holding stuff together. Anyone know where I can get a new mask and hoses for my machine and get it covered under tricare insurance? I hate filing that paperwork myself.

I stopped using the humidifier almost immediately because it was such a pain in the but to keep clean. Since my machine does heat and moisture, am I missing out on the full effects of the device? Any thoughts?

How often should I have a sleep study? Is there a general rule of thumb? How often does insurance generally cover this stuff?

Is there any way for me to know if I'm getting the full benefit from my machine at home or do I have to do a sleep study to find out?

Also, I'm thinking about traveling overseas and I figured I'd need a portable machine for the 8 or 9 hour flight. Anyone have experience with those? Or does an airline actually have outlets you can use in flight?

Appreciate any comments. Thanks in advance.

Tim aka UpDownMostly on YouTube