I have a COT with a ATDN of 35503. Can I change that COT in LD 14 to ATDN of 35516 to make all calls coming in on this COT ring this DN? And can 2 COT lines ring the same DN while AT&T is working on my COT that won't ring on DN 35516. I need to use another COT so DN 35516 can recieve calls on a temperary basis. I'm very new to the phone game and any help is greatly appreciated.