Update2: Tried to move AP but no luck. Instead now took an unused Internet Gateway ( Huawei HG635) and turned it into bridge mode and set the same SSID and passwords. Had to delete the existing Ethernet connection first and set it to internet. Then found some unused Zyxel Powerline adapters and got the AP connected upstairs. Had to put the ‘Internet’ in one of the LAN ports. But handy, can use it as a switch for my desktop upstairs too. So far so good! Had issues with this Ethernet over Power; before in a previous apartment, where the connection would break every now and then.