Show the most correct set of rules post merge

What does this MR do and why?

We currently have an issue where we did not keep track of which rules were applicable at the time of merge, so therefore we don't know which rules we are meant to show or not. We made a change to keep track of the rules applicable post merge, and we need to now show the appropriate rules post merge. However, for the old rules, we don't know which were applicable, and which weren't, so we need to make a best guess.