Why do I have to pair my Bluetooth headset to my Lumia 635 each time my router goes down?

[Windows Central Question]

Lumia 635 - Poor reconnection to bluetooth headset and wifi (when router goes down).

Reconnecting bluetooth headset to Lumia 635. I have to re-pair everytime. Also after a powercut it does not reconnect to wifi automatically

My Nokia 800 connects very quickly to the plantonics explorer 240 headset and reconnects to wifi after a power cut.

Bluetooth is off on both phones except when using the headset

Thanks

Geoff