Some of the other guys can give more info on CTLs and MPSs.
An ACTL (Area Clinical Team Leader) is the TL for a shift. They are the Lima cars (LN, LS, LE, LW) that look after all the crews/stations from their geographical area. For example LS is TL for South which means they are in charge of Emergency (not PTS or ESS) crews from Mitcham, Marion, O'Halloran Hill, Noarlunga, McLaren Vale and Aldinga on their particular shift (South A-E, meaning they follow the same 4 on/4 off pattern as their crews.)
An RTL is different to a VTL. An RTL is a paid staff member who is a Paramedic or above who is in charge of a group of regional stations. They are essentially the same as Metro ACTLs, except the RTL does not follow their 'shift', they are RTL 24/7. For example OS9 is South-East Fluerieu RTL who is in charge of Strath, Goolwa, Meadows and Yankalilla.
A VTL is a volunteer officer who has been elected by their peers to be their team leader. Each station has a VTL and they are essentially the link between the RTL and SAAS as a whole and the station. They do not have their own vehicle or call-sign.
FP1 (Fluerieu Peninsula 1) is the TL in charge of the FP cars. I believe they are a CTL.
The SPRINT Unit (SPRINT Cars, Bicycle Response Unit and Motorcycle Response Unit) have their own Clinical Team Leader too.