Who knows what VIA's on-time performance may be by November, especially in the east, but right now it's not very good. Personally I wouldn't risk a same-day connection with any long-distance VIA train. Last summer I persuaded a friend who was bound for Newfoundland to take the Ocean to Halifax and fly from there. I had suggested that if the train was very late she be prepared to leave the Ocean at Truro and take an expensive taxi ride to Halifax Airport. Well, the train was four hours late into Truro, so she detrained there and made the flight by 10 minutes!
According to the summer edition of Vialogue, the on-time performance ratio in the east was 65% as of spring. VIA's definition of on-time is no more than half an hour late, which is fine. But this summer there have been so many disruptions in service and bustitutions that a same-day connection is risky, especially if the air fare is one of the usual ones where the fare is forfeited if you miss the flight. Cancellation insurance may cover the situation; most policies require a four-hour connection which should be OK in your case. I have an annual policy that is quite liberal in that a two-hour connection is all that is needed, but it's not worth the potential hassle so I prefer to cushion any trip with an overnight stay.