Step off back or forward

Refer to the PBUC Umpire Manual, 6.4 Special Balk Regulations, paragraph(i): "It is legal for a right-handed pitcher to begin a pick-off move to first base by first moving his pivot foot in the dirction of third base provided that he makes a legal step toward first base with his non-pivot foot before throwing there and provided that the move is continuous and without interruption. A pitcher who makes such a pick-off move is considered to be in contact with the rubber when he makes his throw to first base."