Carol is right, there has been no change to Delta's policy (and Delta has gone out of their way to assure SkyMiles members that they are not messing with the program during bankruptcy). Of course there will be instances where only one FF seat is available for a given flight. If so, you may choose to redeem one and buy the other one that you need. But if there are two FF seats available on the routing you want, and you have the requisite number of miles, they're yours.