I have an Edge 540 paired with a Varia radar, so I recently added a Bontrager flare RT rear light to my system. Since the system detected for the first time a low battery it gave me a warning, same like it does with the Varia radar, but even after recharging the battery status stays empty. So every ride it warns me for an empty battery again and again (also red battery icon).
Because of this it warns me also that the Varia radar is empty, so I receive at least 2 messages at the startup of the edge 540, eventually the Varia battery icon will be displayed normal, the Bontrager icon will stay red. When I delete the Bontrager light from the Edge 540 the system is ok, when I add the flare RT again to the system the problem stays the same.
At he moment I'm on the last beta.