Thorn Bird has certainly got that one right.
Indeed, there may be considerably less maintenance done physically on a Class A aircraft, compared to a Class B ---- depending on the System of Maintenance used ---- a point lost on may, based on the fallacious logic of:
"Obviously, if it is A Class, that's better better than B Class"
And, of course, not to be confused with Cat. A.B,C.D,E aircraft for IAP procedures, or A,B,C,D,E,F cat. aircraft for aerodrome classification, or something similar, but not the same, in some countries, for RFFS categories.
Not to mention A,B,C,D E,F,G airspace classes -----
to which A and B were you referring to??
That's what I love about Australian aviation law, it's so clear and simple, so easy to understand, with absolutely no chance of confusion or contradiction, brought about by the complete lack of obfuscating complexity ---- and resulting in the doubtlessly true statement that the pilot in command of an Australian aircraft can always be absolutely confident that what he, she or it is planning to do or has just done, is lawful.
And I believe in Santa Clause, too!! And the statement:"I'm from CASA, and I'm here to help".
Tootle pip!!