I’m having consistent success with a work around.
I get the no signal issue with my trainer every time I ride, but can still get it to work after refining a work-around process. I also have a BLE HR monitor, but I don’t think that changes this issue one way or another, but may be relevant.
What I do:
-Start normally (BLE connections, companion, game…) until you get to the no signal issue on the pairing screen.
-Continue to the ride as if the pairing worked. Obviously you won’t be going anywhere yet because power is not being registered.
-Close the companion app. You will remain in the ride.
-Reopen the companion app. It takes a little time (<1min) for all the connections to resume, but once connected, the connection is stable throughout my rides.
I suspect there is some process in the pairing screen that drops the signal connection after it is made, like it keeps looking for other devices. This process is different because you are already in-game, and it just starts utilizing the signal vs. searching. Of course, I’m just guessing and have no real idea why this works, but it does.