I think someone has been looking at Flightradar and jumped to conclusions. It often shows flights operated on one aircraft to be EIR rather than BE when that is clearly not the case.
The E195 was delayed. Not significantly so - maybe an hour - but a delay nonetheless. Certainly nothing that would necessitate anything being chartered in or money changing hands. Loads did not require an E195, the ATR was sufficient and an aircraft and crew were available. A simple swap. Nothing more to see.