Check your SI letter. The information required for the renewal of your medical and the SI is there.
Here is what is in my letter about the renewal:
"A copy of the cumulative annual PAP device report which shows actual time used. Target goal should show use for at least 75% of sleep periods, and an average minimum of 6 hours per day"
This leads me to believe that 75% is for the entire preceding year. In my case, starting the "treatment" in June, this is not a full year, so there are clearly some guidelines an AME will need to follow prior to issue. For example, I may have been in Tibet, at a monastery with no electricity, learning to meditate for 9 months. Surely that is not cause to deny a renewal?
As a practical matter, I assume an AME can issue with the last X months of reports from a machine. X might be 12. X might be 3. I am trying to solve for X. X might be 0 with a dose of "just make sure his BS story makes sense and he's using the thing now"
SO If I show up in December, and I have my Sleepyhead reports for Oct/Nov/Dec at 100%, and claim the dog ate my other months -- is he able to issue? I would think yes.
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Yes I have a noncompliant attitude. But I still like to know where the goalposts are so I can comply to a letter, if not a spirit of what I perceive to be a cash-grab nuisance requirement.
Yes I understand that my OSA may get worse (particularly if I reverse my weight loss successes of late), and having a machine around may be "neato"
Yes I understand "stick with it" would be a prudent thing to do if I had problems before this mess. Which I didn't.
Since I'm still using the rotten thing, my noncompliance is only theoretical at the moment. I want my 3-4 hours per day spent "sleeping for real" back. The years of my life the CPAP is theoretically saving me -- is being taken out of me today. It's like a reverse mortgage on my health.
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Appreciate any practical insight into the "lookback period" required. Or if these guidelines are public somewhere, some google keywords I can hunt up.