Originally Posted by symbian simian

Just guessing:
Flew from D to A with about 15 pax, the repo for the charter.
Flew from A to B and back full, the actual charter legs.
Flew from A back to D with 130 pax, the repo back to base.

Originally Posted by spooldup

This exactly. Both the repo legs were available for pax purchase and then the charters were completely full for whoever it was.

This isn't the norm, but it can happen depending on what routes are being flown.