I have a Telrad digital key bx system with the following cards installed: 1-COL, 1-OCD, 1-SLD, 2-ELD, 1-HONS, 1-MPD, 1-T1. Can anyone tell me how many regular incoming telephone lines this setup will handle (not including the T1 card). I want to install 16 POTS lines, do I have enough capacity?