Well if someone has TownA and it was registered on 1/1/15, they change the town name to TownB on 2/2/15, then someone else changes their town name to Town A on the 3/3/15. Say a contract was put in place for TownA that was approved on the 2/1/15, then it can be traced to TownA that was registered on the 1/2/15 and not the TownA that was registered on the 3/3/15. Hope that makes sense.