My DS 5007S was programmed to ring the office phone immediately and then the other extensions after a delay. It takes about 15 seconds until al phones (office phone plus 4 extensions) are ringing, i.e extension 25 rings 5 seconds later, ext. 26 rings 5 seconds after that, etc. I think it had something to do with night setting. Problem is, I now need extension 28 to ring immediately. Is this possible?