I got a 955 Solar 8 days ago. Everything about it seems excellent and I've been thrilled, but I am getting neither HRV nor Training Readiness, despite wearing it nearly 24 hours a day (only off during showers) for over a week.
I assumed at first that HRV was a metric that would appear at some point, but that seems to not be the case. I get HRV readings when doing Health Snapshot, and I have clean overnight tracking of sleep, RHR, and Pulse Ox.
I wear the watch on my right wrist while sleeping, but I wouldn't think that matters? Cheers!