So according to TowerTimes and TowersStreet, Sub Terra reopened today after the recent design update. It now has new thigh restraints and a lower locking lap bar, and because of the new thigh restraints large numbers of guests can no longer ride it. They've also said there are no longer actors (which I think has been the case since the start of the season) and the throughput has gone downhill.
Doesn't sound very good at all, but I can only assume this has been done for safety?
EDIT: Just seen on Twitter that they are telling people it's closed tomorrow. Making changes again already?