I’m not sure if it’s the exact same issue, but I have the feeling that it is strongly related.
My Observations:
Pair with 2 BT sources.
Turn on headphones while in range of both - they should both auto-connect.
Disable one of the sources or walk out of range - you’ll hear the disconnect event being announced by the headphones.
Either stay out of range or keep BT disabled for some time - 10 to 30 minutes seem like the reasonable interval for this to happen. Important: If you come back into range or turn BT back on right away, this problem won’t happen and reconnect will work!
Come back into range or turn BT back on.
Auto-connect will not work and I cannot manually connect to the headphones either. It will simply time out. Only a restart of the headphones will make them connect again.
A workaround seems to be to touch one of the controls on the Fairbuds XL, such as the volume up button. This wakes the device and then the second device can connect again.