Regulation 20 Alteration of scheme rules

affect any of the matters dealt with in Part III of the 1993 Act (schemes that were contracted-out etc. and effects on members’ state scheme rights), or any regulations made under that Part, that relate to guaranteed minimum pensions, in a manner that would or might adversely affect any entitlement or accrued rights of any member of the scheme acquired before the alteration takes effect;

affect any of the matters dealt with in sections 87 to 92 of the 1993 Act (protection of increases in guaranteed minimum pensions) or sections 109 and 110 of that Act (annual increases of guaranteed minimum pensions) or any matters dealt with in regulations made under any of those provisions; or