Android reboot - bt connection lost

HI,

I know there are several threads on Bluetooth already.

However, I previously never had an issue. Recently (it might have coincided with the latest GPS Software update) my F6xSolar does not reconnect to the phone after the phone reboots. I always turn of the phone during the night.

Since about 2-3 weeks now I need to deactivate Bluetooth on the phone, enter GC then reactivate Bluetooth and wait for 20sec. Then the watch connects.

If I do not do this, the watch never will connect during the day.

There was no change on my phone, no software update, GPS is on. 

I do not know what the reason could be. GPS Software update is unclear to me, as I did not consider this to impact bt stability.

Does anyone know what the cause could be and what solution I could attempt?

Thanks,

JP