"A college 7s tournament is generally hosted over 2 days, Saturday and Sunday. I don't think any 7s host is eager to move from a Sat/Sun schedule to a Fri/Sat schedule."

There are a few Saturday only tourneys -- the West Coast 7s hosted by Cal Poly is one example -- but it is highly doubtful any two-day college tournament would move to a Friday-Saturday schedule. The teams would have to travel on Thursday and compete Friday thereby missing two whole days of classes.