mon 28 return flight to perth cancelled

I got a txt from Jetstar today to tell me my return flight to perth from melb after xmas had been cancelled so I rang them and they put me on a later QUANTAS flight back to perth, 08.30am --it seems a bit weird that I was flying to melb with Jetstar then I got put on a quatas flight at a earlier time 0.600am --coming back I was booked on a Jetstar flite then I was rebooked on a quantas flight to come back to perth --I SEE A PATTERN HERE