In general
A plan shall not fail to be treated as described in clause (i), (ii), (iii), or (iv) of section 219(g)(5)(A) (and shall not fail to be treated as satisfying the requirements of section 401(a) or 403) merely because—
(A)#
the plan fails to obtain payment from any participant, beneficiary, employer, plan sponsor, fiduciary, or other party on account of any inadvertent benefit overpayment made by the plan, or
(B)#
the plan sponsor amends the plan to increase past, or decrease future, benefit payments to affected participants and beneficiaries in order to adjust for prior inadvertent benefit overpayments.