It was bound to happen, given how the timeline advancement worked in MW5:Mercs. The story covered the Third and Fourth Succession Wars (2866-3025 and 3028-3030), the typical starting point for Battletech before the lore, politics, and tech get too complicated. The Clan Invasion (3049-3052) is the most iconic part of the timeline, I think.
I live to talk about Battletech, so hmu if you’ve got questions!
Sarna.net is the very good wiki for the BT universe.