Since the update has been made available for the FR165, I've tried to install it to my partners watch via Wifi. This is the procedure I use myself updating my Epix. The download takes a minute and is very reliable. (I participate in the beta program so have some experience with updating)
So using the system menu, check for software updates, the FR165 connects to Wifi. It checks for updates and starts downloading. After a long while (5 minutes?), it pops up with an error message stating that it failed.
Anyway, not the end of the world. I managed to do the update via the connect app, and that worked perfectly but took some time.
Any other users have a similar experience?
The update seems to fix some low HR readings during some cardio fitness as well (or maybe the reboot fixed it).
My partner loves the watch!!!