Unfortunately, the alternative format doesn't sell well. Even in markets where it gets great ratings, the format underperforms other genres. This is obviously why the WBRU board voted to sell the station. I expect that had it sold to another commercial broadcaster, they'd have made some changes in the format.
And with so few profitable format holes in most markets, a station that's been locked for many years into a format that Madison Avenue now believes appeals to listeners reluctant to respond to advertising probably won't get much interest when put on the market -- certainly not from anyone looking to get into a bidding war with EMF, which rakes in so much money from the weak-minded and superstitious that it need never worry about losing such a war.