Regarding the list of 604's, here's some further info.
HZ-AFA2 fully manned
HB-IVV fully manned unless recent change
A9C-BXB DON"T GO THERE, owned by BEXAIR - STAY AWAY!!!
P4-FAY I believe is fully manned
If you can get hold of a Challenger operators handbook, the contact information can be obtained in that.
Good luck
