If airlines are willing to book a 50-minute (or 40-minute) connection at GVA, then they have convinced themselves that they can transfer people and bags between aircraft in that amount of time. You should not be concerned about it.
AC's on-time performance is what will likely cause a problem. So far, AC's YUL-GVA flight has been on time only 50% of the time in July, with delays of several hours being common. AC422, which you are presumably also booked on YYZ-YUL, has an even worse record: it has only been on time 5 times so far this month, although it may be possible to get on another YYZ-YUL flight if there is one operating and there is space available (you can't count on either of these). These stats are based on flightradar24, and they consider a flight on time if it touches down within 15 minutes of the scheduled arrival time, which is generous because then the plane has to taxi to the gate. The point is AC is very unreliable right now.
AC is unlikely to change anything for you for free unless a connection gets below the minimum connection time.
Other than not booking the itinerary in the first place,
Originally Posted by
Stranger
Let the airlines sweat this out. If they sold it to you, it's for them to handle issues.
this is the best advice. There are later flights on TK between GVA and IST, and there are other ways to get you from YUL to IST if you miss the transatlantic flight. Worrying about it isn't going to change anything. It's AC's problem to get you to IST.
If you fly the actual booked itinerary then you won't need to recheck luggage. However, it's a bit hit-and-miss what happens to your bags when you are rerouted. Carry-on only is best if possible; if not, make sure you have a few days of clothes, etc., in your carry-on.