Anne, 330 will adopt you and any one else on your team
back on topic,
I was a student for 3 years and then a mentor on the same team for the last 2. Now, I'm getting ready to leave my team to transfer to RIT.
This year we only have 1 senior, though he was the leader. In the past though we've always seemed to lose the 2-3 most important students, but always seemed to rebound. Since our team is only 12-15 students losing the 3 most important ones is quite a bit.
My take is that if you have good adult leadership, losing seniors isn't going to matter. I've never been on a completely student run team, but I would imagine that losing their leaders would be much more devastating.