auto enrollment for pre-12/29/22 plans and LTPTE

My understanding is that for a plan started before SECURE 2.0 (and therefore grandfathered in for not being required to have automatic enrollment if over 10 employees), if they add an automatic enrollment provision voluntarily, then LTPTEs are not subject to the automatic enrollment.  I don't see anything in the proposed regs that counters this.  Am I correct with this?  Thanks.

If a plan sponsor adds an automatic-contribution arrangement and wants it to apply to less than all eligible employees, one might specify carefully which employees are benefited or burdened by the implied election (or which are not).

If the plan sponsor uses IRS-preapproved documents, one might evaluate whether a particular set of documents allows enough choice to specify the intended provision without defeating reliance on the IRS opinion letter.