What's the winning box for the King in a Queen against 7th rank Bishop-pawn endgame? In a Queen vs Pawn endgame where the pawn is a Rook pawn on the 7th rank, it is a draw unless the King is inside the winning box, as shown here:

My question is what is that winning box if the pawn is a Bishop pawn? Though I do know that the Queen needs to be on h2 or d2 against an f pawn, and on a2 or e2 against a c pawn. (Comparing to the whole 2nd rank if it was a Rook pawn).
There are actually two zones, depending on which side of the pawn the black king is. If it's already in the corner, the zone is small:



If the black king on the other side (towards the center), the zone is larger. The white queen can force the king to stand in front of the pawn, giving the white king an extra tempo to reach the 'small' zone above. (This also applies if the king is in front of the pawn already.)



(diagrams from Fundamental Chess Endings by Müller and Lamprecht)