At that point, no one (aside from a few people) knew or expected what was going to happen later that year.
I would not expect UE5 to come before 4.27 at least, if there is no 4.28 it probably will come whenever 4.28 would have come. (remember, 4.27 wasnt on epics roadmap either, it was 4.26 and “4.26+”.)
That said, a heads up from Epic on this would be nice. Its not like anyone will be angry, but its currently quite troublesome to plan anything.