It may move any turn, and still transforms into a strong piece. However, this would waste so much time it probably wouldn't pay off anyway, since a player doing that increases his army, but slows by half its efficiency. Of course, making the other player moves his King on a even turn, makes him loose a promoting turn. A pawn on the last rank cannot move. That is especially bad, since the other player can use it as a protecting wall.
All men move as in chess, except there is no castling or en passant.
Movement is compulsory, and once his king is captured a player loses. A pawn on the 1st rank may move 1 or 2 spaces if not capturing. A pawn on the 8th rank may never move again, but can be captured. We would like you to specially notice rule 5. This is not a common feature in Chess Variants, but may be an excellent concept to extend.