PBGC rate to 120% PBGC rate

[Gary]

A plan changes lump sum interest rate from PBGC rate to 120% PBGC rate for distributions over 25,000.

Is there a deadline as to when this change can occur without having to be concerned over 411(d)(6) cutbacks?

Or another way of putting it. Is there a point in time when making this change would require anti cutback provisions applied to accrued benefits? i.e. where the accd ben must be based on 100% PBGC rate and not 120% PBGC rate. And where wearaway issue can apply.