I actually think the issue with the phone not connecting is due to the way the ignition works in the car.
Normally most things in a car are started when you start the engine, including the infotainment system, but in the EX30 it's when the car is unlocked.
If say you don't get straight into the car, you load some things into the boot, or go to disconnect the charger etc., your phone isn't necessarily going to be visible to the car when the systems in the car start up, therefore it's not seen and doesn't connect, or if it does connect it may get disconnected.
I think the issue is the lack of reattempting to connect. If the car could just try to reconnect when say you put it in Drive, then I don't think it'd be a problem, but it doesn't ever try to reconnect unless you do so manually.
I have found when I just get straight into the car as it unlocks, the phone generally connects ok.
