moose;416349 wroteComp nailed it.
No luggage - download your boarding pass to your phone. No need to check in. Go straight to security. 20 min before flight tops (serious).
That might be cutting a bit too fine, even for me. However Moose is quite right, their 2 hours ahead for Hamilton or London when not checking any luggage is ridiculous. Make sure you do the web check-in 24 hours ahead of flight time, either save your boarding pass on your phone or you can also print it at home (just to be safe). After clearing security, wait until last call for boarding and the line is gone before walking up to the gate. No use standing outside in the cold.
Even after clearing the gate in Hamilton, their is a small area still inside where you can watch the lineup to get on the plane until it almost clears before you go outside.
Hint: Make sure your boarding pass name matches your passport. lol, it could have caught me.