Follow-up visit with Pulmonologist

Went to my follow-up appt with the pulmonologist about the 2nd sleep study. He is putting me on an Auto-pap. He said he would not clear me until I've been on it for 90 days and I have to follow the 90/70 rule. I have to use it at least 90% of the time and 70% of the time I have to do it for at least 4 hours. This sounds hard. Is it going to be? Also, does anyone here have experience with an Auto-pap?