For purposes of determining the minimum contribution requirement under section
1423 of this title (before the application of section
1423
(b)(2) or (d) of this title) the plan sponsor of a plan which is overburdened for the plan year shall apply an overburden credit against the plan’s minimum contribution requirement for the plan year (determined without regard to section
1423
(b)(2) or (d) of this title and without regard to this section).