I think if an option is there, then it can be used.
Well, quite.
The version on the website still has the help you to bugger off elsewhere option in, but it is the weekend, I suppose, and it may not be the version with which the actual offer holders are now being presented, but if it is, there's no rush for them to accept the possibility by firming, as the deadline for offer holders' decisions is still 4 months away.
It just seems to be a very odd thing to have put in, with no indication of how it would be achieved. Guaranteeing you a place on the same course, at the same college, for 2022 entry and Giving you a place on Course Y instead of Course X, and / or a place in College B instead of College A, but still starting in 2021 are obviously totally within Cambridge's control. But getting the student a place somewhere else? Or have other universities popped up with, It's okay, Cambridge have approached us about this and we've agreed to take their overspill, on the course of the applicant's choosing, with guaranteed accommodation (even if we don't guarantee it to our own insurance entrants)?