I've been playing this mod for the longest time and basically taken the Byzantine Empire and taken over the whole map with them. but now i want to either become king/emperor, or rebel against the faction so i can take over and lead myself. it doesn't seem to give me an option to do so.

It gives me the option to be released from my oath, but i'll lose all the fiefs ive gained(which is a lot, and a lot of soldiers), any ideas?