ThankQ planefag.
I can answer the callsign question.
Good night!
Military Callsign Prefixes
RCH#### = 'Regular' transport callsigns, abbreviation of REACH
PAT### = Priority Air Transport
SAM = Special Air Movement or Special Air Mission
SPAR = Special Priority Air Movement
CNV#### = Convoy, used by Navy transports e.g. C-40 (version of Boeing737). Same role as Air Force C-40s to transport primarily personnel and/or light freight
There are other prefixes. We see the LOBO prefix pretty often. We have been told by milfags that different units have different schemes for assigning callsigns to their aircraft and missions. I don't know a specific meaning for LOBO* but have seen it fairly often.