Looks like progress s being made. I think you are mixing up some of the terms. Pull stations, smoke detectors, and other alarm making devices connect to Initiating Device Circuits (IDC) or called sometimes zones. NAC is short for Notification Appliance Circuit which is where the horns and strobes connect.
Check the area that is Zone 1 for stations that might be pulled or damaged. There also could be a smoke detector in alarm somewhere. Don’t know what type pull stations you have. If they are the Simplex plastic T-bar stations these can be damaged if someone tries to stop an alarm after the station is pulled by pushing the T-bar back up. That either breaks off the plastic button on the switch inside or breaks the parts holding the T-bar in place.