Why is my Nokia Lumia635 switch to airplane mode before rebooting to start update to Windows Phone10

[tbrat14]

View attachment 97026 It does it here when it gets to 1 on the count down

 

[Harrie-S]

View attachment 97026 It does it here when it gets to 1 on the count down

Not sure, but people reported that the "slow" also does not work.
I would first suggest that you download the windows recovery tool on your ps and than try the fast.