ADP Test: can switch from prior to current after EOY

When running the ADP test, I recall it's easier to switch from prior to current year testing than vice versa. I also recall that it must be done by end of the plan year.

I'm curious if there are options to change it from prior to current after the end of the plan year?

Hey, could that be interpreted as a new-fangled amendment increasing benefits, because it helps the ADP Test?

My understanding is the IRS position has been that this is a discretionary amendment that must be adopted before the end of the plan year to be effective for the current plan year. But maybe that IRS position has changed since SECURE or SECURE 2.0; if it has I would love to know that, as it could be a useful tool one day.