Just another thing to mention based on the last couple of years...
We've previously got to the tunnel check-in barriers and found there's space on the earlier train rather than the one we'd booked on. Some people went with what was booked, whilst some went for the first available train so the group got split up. We managed to rendez-vous again in France but its easiest if we all stay with the 07:50 train should the same thing happen again...
