If, after the payment of the New Jersey estate tax, there becomes due and payable a tax upon any future interest in any property under an instrument that creates an executor device or an estate in expectancy of any kind or character that is contingent or defeasible, or if by reason of any additional or corrected assessment by the Director an additional inheritance, succession, or legacy tax becomes due and payable, the tax paid will be credited against the tax arising therefrom, but the amount so credited will not in any event exceed the amount of the tax so accruing.
N.J. Admin. Code § 18:26-3A.9