Early Retirement Window in Pension linked to a Nonqualified Plan

We have a defined benefit Pension plan and we're going to do an early retirement window where people get extra age and service if they retire during a specific period of time.  We also have a defined benefit nonqualified plan that is linked to the Pension and provide additional benefits in excess of what is allowed under the Pension.  The benefit someone receives under the nonqualified plan is directly affected by the benefit one receives under the qualified Pension (i.e., the more someone gets under the Pension, the less someone gets under the nonqualified plan).

We don't want the nonqualified benefit to be affected by someone taking advantage of the early retirement window.  In other words, just because I'm getting a larger benefit under the Pension for participating in the early retirement window, we don't want that to result in a lesser benefit under the nonqualified plan.

Are there any issues with amending the nonqualified plan to provide the early retirement window benefit doesn't affect the benefit under the nonqualified plan?

As long as the time and/or form of payment isn't changing, just the amount, I don't see any 409A issues.