Send the UR closing message to the user when the map really gets updated (contains all changes up to the UR "closing" time).

Some things may get fixed immediately (by adding a closure or updating a place), most things require a map update. That means that we always have to write stuff like "in few days/after the next map update, the problem will be fixed".

Maybe a third button like this:
"Mark as Solved"
"Solve on map update" <-
"Mark as not identified"

When the second button gets clicked a form opens when I can write a message to the user, and you just need a third email template where to put it in and to place the email on a queue, which gets sent when the map update succeeds (you could even put multiple replies in one single email, to avoid spamming the poor users doing a lot of reports).