The system is primarily Phase I and will remain so for the Public Works TGs. EMS TG 1077 is nominally Phase II but the dispatcher is usually Phase I. TGs 1072-1077 switch between Phase I and Phase II depending on if a Phase II unit is active on the TG.
The typical pattern on TG 1077 seems to be that the call dispatch, which is patched to VHF, is Phase I. When the ambulance responds on the TRS it is Phase II but reverts to Phase I when the dispatcher acknowledges and remains Phase I for the remainder of that exchange. It is a similar situation if a Phase II ambulance is on the TGs 1072-1076 that are patches to VHF Fire.
Basically, the system is Phase I unless a Phase II unit is transmitting on the TG.