atcomsystems.ca/forum Forums Other TDM Phone Systems ESI Telephones & Systems Cordless analog extension

Try routing the calls on both your lines to an all ring department (Function 33) with the cordless phone as the overflow destination. You'll lose the ability to flash a call wating on the digital phones but maybe you don't need that. I don't have time to test it but it might work.

Workarounds like the above tend to work differently with each s/w version. That's why ESI says "not supported"