Equity Aviation Services handle all MANGO flights at all destinations. They were informed about the subsequent aircraft change.
Apparently, Equity did not have enough staff on duty to service the aircraft. Apron Control wanted the DC9 off the parking bay ASAP, thus the baggage accompanied the aircraft to the hangar.
The baggage was off-loaded this morning, and delivered to all the passengers by Equity Aviation Services.
Source: MANGO OPS