Need explaination for illegal touching in NFC Championship

[Johnny Cakes]

The last play of the first quarter in the NFC Championship game involved a punt. The kicking team player (New Orleans) when out of bounds while running to cover the kick; the official's hat was removed signifying that. The same player was the first to touch the ball and the official threw the flag for illegal touching.

However, the penalty was withdrawn with this explaination: "No foul on the play as the quarter expired prior to the man touching the ball."

How does time expiring during the punt change whether there was an illegal touching?