If one of rook pawns has not yet arrived to seventh rank, draw is still possible but three conditions must be met:
a) black king supports more advanced pawn,
b) white king is too far away to enter winning area seen in example 12 and
c) white king cannot neutralize the a -pawn.
When “backward” pawn is on a3 Black can draw if white king is not inside area bounded by squares c1-c5, d6-h6, including squares a1, a4, b3 and b4. We can see such example in study by A. Cheron from 1945. White to move cannot win!