Yet another step to fully merge the 2 carriers has occurred. I'm currently listening to Calgary ATC and former Canadian flights are now using Air Canada as their callsign, rather than Canadian. Flight numbers still have not been adjusted (ie still start with 3, as in 3***). I understand Air Canada has been granted the single operator certificate by the Canadian Government. Regional flights are continuing to use their original callsigns. An interesting note, some of the pilots are replying to ATC simply with the flight number. Can only guess if they are doing it just to save time or if it's difficult to change to something that has to be most un-natural to them after all the years using "Canadian".