It is finally working on both my and my wife's phones. My confidence that it will continue to work is, unfortunately low. I am careful to always have the key card with me, just in case. Happily, I have not had to use it in over a week.
I appreciate this cautiously optimistic report. I've seen a lot of people report that after a day all is working fine, but in my opinion it's probably best to wait at least a week before declaring victory.
Unfortunately I don't have a Model 3 to share my own phone as key experience, but I would like to share some recent Bluetooth experience that shows, in my opinion, just how unreliable this technology is. Now I admit that this is a generic Bluetooth issue, and not really the exact same BLE technology that the key works on, but my experience is this, and just shows you how different devices will behave quite differently:
With my previous phone, my Bluetooth experience in my LEAF was pretty poor. It would take forever to connect, and occasionally it would fail altogether, requiring a manual reconnect, Bluetooth off/on or Airplane mode on/off to reset.
Then I got a brand new phone, and if it could get any worse, it did. The connection issues continue, and now add in some "skipping" behavior, and the fact that 50% of the time instead of resuming playback where I left off, it resumed playback from the LAST starting point. Again, I realize that this is not a phone as key issue, but just goes to show you that somewhere--either on the phone side or the car side, there is something screwed up.
So my LEAF has been in for service for almost 2 weeks, and I've had another Nissan loaner. The Bluetooth connection on this car, until today, has worked FAR better. I've had no connection issues, it's resumed right where I left off, etc. Aha! Must be the LEAF Bluetooth implementation is to blame.
Well, this morning, the loaner vehicle's Bluetooth acted up. I was getting random connects/disconnects, skipping on the audio, etc. It was horrible. I turned my Bluetooth off and on, and then it started working like a champ again.
All that is to say that even under the best of circumstances, there are still issues with Bluetooth, and so many different variables (different brands of phones, OS'es, versions of OS'es, etc.) that I just think it will be a miracle if this ever works reliably.