Additional information about which detailed type of ASM this is.
Legal values
NEW Inserts new flight (leg) information.
CNL Cancels, but do not remove, one flight or flight leg. The flight (leg) can be reinstated.
RIN Reinstates a previously cancelled flight (leg).
RPL Replaces all existing information for the relevant flight (legs).
ADM Updates only the given information for the relevant flight (legs).
CON Updates only the given information for the relevant flight (legs).
EQT Updates only the given information for the relevant flight (legs).
FLT Updates the FlightId of the given flight (leg).
RRT Changes the endpoint of a single leg flight, or changes the routing of a multiple flight legs. The DepartureAirportIATA of the first leg can not be changed.
TIM Updates only the given information for the relevant flight (legs).
Comments
The description of the values above is standard IATA. Systems can implement different rules, for instance handling NEW as an update if the flight leg exist, or handling RPL and RRT the same.