A. No it isn’t. But you have to give the Rabbi enough time after the holiday to repurchase the Chametz back from the non-Jew he sold it to on your behalf. The form says one hour just to be sure it was taken care of. Online actually (if you used the Chabad.org form) it says to wait two hours, because it is sold by time-zone, and holiday end times vary quite a bit within the time-zone and this way it gives them enough time to cover any locale that may have sold through their service.
