@Ramaly You will need to enable Remote Management on the ER7206 ( see user guide page 248 ) . You will need an appropraite subnet and mask to define what IP range you wish to allow access from ( or...

@mistoffelees I'm afraid I can't answer that, I only ever used the ER605 in stand alone mode.

@mistoffelees Have you tried using the MAC address clone ( page 33 of the user guide ) to clone the address of your Macbook. Its possible Ting insist on the connection having a fixed MAC address.

@FlameOtter USB tethering to a mobile phone requires that the router supports RNDIS. The ER605 (and I assume the ER707) are based on quite an old version of Openwrt and do not have support for RNDIS....

@MR.S it may be that tp-link has fixed this now, From @ITV s experience It would appear not Did you ever check the MAC address being presented on the WAN interface with something like Wireshark ?

@ITV @MR.S I think there is something with the hardware that creates a conflict, it applies to completely identical routers with the same hardware version. you can use an ER605v1 and an ER605v2...