The advice previous to this has been good.
I suggest you make friends with some of the guys. On group rides that I've been on, if you have a flat or a mechanical, a friend or two generally stop and help.
on a bigger ride, they generally do not wait up, so you are better off staying with your smaller group.
So it helps to be friendly with the other riders. DO get a route sheet in case you get lost, it DOES happen even with the best ride leaders.