This may not be a bug so much as the game behaving in a way contrary to what it "feels" it should.
Let's say you have multiple hires available (like if you had to send your queen on a 38 hour cruise to avoid a martyr for example) and you queue up a series of all 3 uses over time with a promotion in the 1st or 2nd choice.
If you cancel the promotion (or it's otherwise prevented from happening), sometimes (usually?) the other specialist(s) in down the line in the queue can get changed to different personnel choices.
Maybe this is related to the fact that the specialist order reverses when they go from future to active? I don't know.