Before iOS 14, I had a lot of hassle switching between devices while wearing my AirPods Pro. I had to keep moving the Bluetooth connection back and forth manually.
In iOS 14, they totally nailed it. I can (and do) use both my iPhone and iPad side by side, and the handoff works almost always the way you would want. (I don’t know if they call it “handoff”, but that’s exactly what it does…)
I haven’t totally analyzed it yet, but it seems to work like this:
- You start with device A playing audio via AirPods.
- You pick up device B and start using it: AirPods remain paired to device A, which is still playing audio
- You continue to interact with device B, but now start audio playback on device B as well: AirPods flip over to device B. Device A notifies you that your other device hijacked your audio.
- You start playing some audio on device A, then AirPods flip back to A
So it’s not sufficient to interact with the new device; you have to also initiate audio playback on it before the AirPods will decide to jump ship. Obviously, if you play back audio on two devices at the same time, only one will work. Fortunately, you would never do that 
Having said this, Big Sur does NOT handle this gracefully. It tries, but fails. I hope they fix that soon. Really seems like a major QA failure to not have coordinated that rollout properly.
Meanwhile, in the world of my mobile devices, I’m much happier