Alternatively, if I format the SD card and then plug it back in, how long should I wait?
I tried out a new mask last night and some pressure settings changes. I forgot that the SD card was still in my computer, so the machine ran without it. This morning I wanted to see how I did, so I inserted the card back into the machine and waited at least 15-20 min. Checked the card in both SleepyHead and ResScan... but data is missing. SleepyHead shows nothing for last night. ResScan shows the whole night in the summary graph, but it only has detailed graph data for the first short session where I was playing around with the mask. There's no data for the other session(s) from last night, including the main (sleep) session.