I doubt there's a definitive answer here. It could limp on for the necessary few weeks or it could disintegrate completely tomorrow. In my experience of terminal release bearing problems, sooner rather than later is more likely.

You can help matters by performing clutchless changes where possible (i.e. once it's moving). Presumably if you're trying to avoid changing the bearing before getting rid, the synchromesh cones don't owe you anything either :-)