HH
I believe the distinction comes when a particular seat is sold to someone not associated wth the company chartering the aircraft, ie. the aircraft is available to the
general public, if one mining organisation charters the entire aircraft for their crew, even if its at scheduled times it's still charter.
From the link in my above post:
"[charter substitution] may occur where the person who the passengers have contracted with is not an aircraft operator at all, but publicly offers to arrange flights with (charter) operators in accordance with fixed schedules, to and from fixed terminals."
To me this states that a situation in which a 3rd company (not an aircraft operator at all) takes the booking's for what appears to be an RPT operation and then charter's the entire aircraft is illegal (except with special permission). As also stated on the casa page this is to eliminate any situation whereby to the public it would appear that they are on an RPT op but they are not.
"CASA is aware that some charter operations are conducted in circumstances which have many of the hallmarks of RPT operations, and which are indistinguishable from RPT operations by the travelling public"
However as bushy point's out this legislation appears not to be consitently applied across the industry.
My 2c
MHA