(b)any person who holds or may subsequently hold money on account of such dealer, to deposit in the Treasury, either forthwith upon the money becoming due or being held or within the time specified in the first mentioned notice (but not before the money becomes due or is held as aforesaid) so much of the money as is sufficient to pay the amount due from the dealer in respect of the tax and penalty under this Act, or the whole the money when it is equal to or less than that amount.]