EACA Covered Employees / Uniformity Requirement

[Gruegen]

A plan has a 6-month service requirement for 401(k) purposes and a 1-Year service requirement for matching contribution purposes.

The plan is considering adding automatic enrollment of 5% for newly hired employees only. Further, the Plan wants to be considered an Eligible Automatic Contribution Arrangement (EACA).

Can the 5% default contributions be delayed until the participant is eligible for the match (1 Year) or must the 5% automatic enrollment be applied once employees become eligible for the 401(k) (6-Months)?

In other words, would waiting to automatically enroll participants until 1-Year of Service violate the uniformity requirement of Treas Reg 1.414(w)-1(b)(2)(i)?