Thanks for the references to 139....lets have a look at them...
139.400 and 139.405 reflect the creation of the CA/GRO but that service still needs to "meet the standards for a CA/GRS set out in the Manual of Standards" (139.410)
And that MOS reflects MBZs not CTAFs. 139.390 Definitions:
"air/ground radio service means an aerodrome radio information
service that provides aircraft operating in the MBZ of an aerodrome
with the services and information specified in section 14.2 of the
Manual of Standards."
"certified air/ground radio service, or CA/GRS, in relation to an
aerodrome, means an air/ground radio service for the aerodrome
certified in accordance with regulation"
And if the people running the show don't know exactly what regs they operate under, how then can they comply?
If that is bush lawyer speak, so be it, but "Rules is Rules Macca" and it would ba a "can O worms" if the holes in the cheese line up.
If it looks like a shonk...