I’m still under Android 10 on my Fairphone 3 (I had no proposal to migrate to Android 11 for now).
But for some weeks now, I encounter some instabilities in the Bluetooth connection and it not seems to be linked with any OS update.
Here is what happens:
I must generally tap 2 or 3 times on the Bluetooth icon in the shortcuts’ bar at the top of the screen to succeed in activating the Bluetooth.
Recently, the Bluetooth sometimes disconnects itself automatically after a few hours. (That’s annoying as I’m using the French Covid tracking app that requires a permanent activation of the Bluetooth when I’m away from home.)
The Bluetooth on / off problem was a known “feature” of last year’s Android 10 patches. See here for example.
Presumably something has happened a few weeks ago in your setup that has triggered it. Try Safe mode. That won’t help but will confirm that it’s a user-added effect that could be corrected by a reset (not what you want to do but if you’re backed up you should be OK).
About getting the Android 11 update: did you contact FP support and SFR too? If you get them both working on it they might meet in the middle.
The issue seems not to appear in Safe mode ;-).
As you suggest, I’m going to contact Fairphone support and SFR in order to go further in my upgrade issue.
Regarding the upgrade issue, here is the answer from Fairphone support:
Unfortunately with the latest update, there were issues with compatibility and the SFR network infrastructure.
Therefore they have not pushed the update onto its users. They fear that there maybe be connection issues if done. They are the only carrier in Europe to have this issue, and we are looking to resolve this with our next update. We apologise for the delay, and thank you for your patience!
.