shall, for purposes of this subchapter, be treated as welfare plans rather than pension plans. In the case of any arrangement or payment a principal effect of which is the evasion of the standards or purposes of this chapter applicable to pension plans, such arrangement or payment shall be treated as a pension plan. An applicable voluntary early retirement incentive plan (as defined in section
457
(e)(11)(D)(ii) of title
26) making payments or supplements described in section
457
(e)(11)(D)(i) of title
26, and an applicable employment retention plan (as defined in section
457
(f)(4)(C) of title
26) making payments of benefits described in section
457
(f)(4)(A) of title
26, shall, for purposes of this subchapter, be treated as a welfare plan (and not a pension plan) with respect to such payments and supplements.