I also downloaded the updated companion app. I started a 90 minute workout and all was working well until the 80 minute mark. All connections were suddenly lost. I then reconnected directly to the Apple TV and it worked fine until the end of the workout. After I did the reconnection I noticed a message stating it was reconnecting erg mode.
This is all very frustrating and I feel I can’t rely on using the product now without facing some sort of problem. Until the last companion update I had been using zwift with no problems for 3 years.