When does the clock start? (NF)

[BktBallRef]

From another forum:

"This past week, I had a Varsity game in the State of Florida (Federation rules). On fourth and 10 with two and a half minutes left in the fourth quarter K kick the ball and it touched beyond the expanded neutral zone and muffed by R and recovered by K. The linesman had a live ball foul illegal procedure on the play, so R elects to raplay the down with K penalized 5 yards.

Here is what Happened,a nd I am sure we got it wrong, but my white cap is bull headed about having the play right. He elected to start the clock on the ready for play. I stopped the clock and ran to the ref and questioned him about starting on the ready, I thought it should start on the snap, because the result of the preceding play dictated a starting on the snap. He negated my question and said it should start on the ready. I then brought to his attention the first down clock rule.... if on first down of a new series the A team commits a foul and the down is replayed... the clock runs as governed by the flagged first down play. Still he is adament on starting on the ready."

When does the clock start, on the ready or on the snap?