I just tried to do the update on my Epix Pro gen 2 and it fails at the very end to install. I even tried the Garmin Express software update route plugged into my computer and it also failed. I don't think this update is ready for prime time for the Epix 2.
Mine EPIX PRO 2 updated fine over wifi. It was showing update available, I approved it, and it went well, with auto restart afterwards. What I noticed though was a huge volume increase on voice alerts during activity. I didn't had the phone with me to adjust that and had to bare with it for almost two hours. I hope things fixed will make this update useful.