Field Officers that you see in the street do work the EMS Chart and are assigned A/B/C plattons. The HQ and some of the Division staff are assigned to "D" which can be M-F, T-S, S-T with holidays off.
For the most part they ride alone. There were some programs in the past with the Boss and a Medic together as a ALS non-transport/Supervisor unit. But they didn't work out.