Following two nights with the CPAP machine, the watch said this morning:

Although I didn't feel that good today. The SpO2 graph had a few dips and the snoring time was low:

Deep sleep was good, so actually the thing that correlates with feeling better was lack of deep sleep!

I think for the next steps I'll continue using the CPAP machine and monitoring my sleep with the watch. Then perhaps I'll work out how to download the raw data and do an analysis.

At some point the sleep specialist that I've been referred to will get in touch. A new CPAP machine might help, as my current one is nearly 20 years old!

I'll carry on trying to lose weight too, and see if that leads to any improvement.