Yes: we established them a bit early so we had more factions to play. In addition to others who were around longer than in canon like the Principality of Rasalhague.
If you look from the page
https://www.sarna.net/wiki/Factions between the Second Exodus (2242) and the Age of War (2398), there are quite a few factions at play:
Inner Sphere (Major): 6 (2242), 6 (2398);
Inner Sphere (Minor): 28 (2242), 2 (2398);
Periphery: 5 (2242), 5 (2398);
Deep Periphery: 3 (2242), 5 (2398).
So compared to the 11 factions you predicted, in 2242 there would be 42 and in 2398 17.