Unless someone else is using A4 27 (I'm not now), that's not fixed, but the opposite. There, ideally, shouldn't be 'a' suffixes where such things don't belong.
Plus there's this:
SOP in this situation in my understanding would be to include an updates entry due to the renumbered exits instead of doing the XXa label to preserve in-use labels.
which is what I thought too.
This is why I listed the points where people ought to tweak their list entry to have the new label, and then did it on my own .list.