I have DHCP enabled with Address Reservation.
So I have my android devices MAC addresses bound to specific ip addreses.
After a restart any android device will be trying to connect but without success.

If I disable temporarily the address reservation on that particular device it will connect succesfully. 
I also have an older Archer VR600 v1 which has the same configuration and works flawlesly on that matter. 
This looks like a bug. I have tried to play with different settings and forget the networks on the android devices with zero success.
I am not the first one that this is happening to. What is the cause of this?