From what I understand you don't have to be displaced to bid to another category as long as you're seniority can hold it (as long as you're talking f.o. to f.o. or capt. to capt.). I know it's B.S. but from what I was told by planning is that as long as someone senior to you bids a new position and they can hold it they are entitled to that new position. Even though you bid the 50 with a conditional bid, if you are not displaced out of the 70 then it does not matter what conditions you had in your bid. Like I said earlier the percentages apparently have nothing to do with bidding out of a specific seat, only into the seat during a displacement. (I've had a few drinks so maybe only I know what I'm trying to say!)