SoRCon 11 23-25 Feb 2018 Basildon UK http://www.sorcon.co.uk
British Player cannot win via a siege of Quebec. (remove this victory condition).
It's been proposed as a game end, but not necessarily game winning, condition, but I'm not sure if anyone has proposed carrying on or not. There are four major issues:
History. The loss of Quebec was the beginning of the end for the French, though they did also have to lose Montreal to put the final nail I'm tje coffin.
Points swing. The 22 (which can be increased to 28 if carrying on) point swing is a lot for the French to overcome. And if carrying on it's worse, if the British can take Quebec, they can probably take mote quickly.
Supply is traced from Quebec, so those rules need changing if carrying on. But how to change them isn't obvious (adding Montreal leaves Nova Scotia unsupplied).
Quebec is a critical card due to its settler symbol. Losing that hurts, a lot - possibly even terminally.