Testing day.
(6) Testing day. The term testing day means any day on which 1.410(b)-8(a)(1) requires any plan (within the meaning of 1.414(r)-8(d)(2)) of the employer actually to satisfy section 410(b) with respect to plan year that begins in the testing year. Thus, if a plan is required to satisfy section 410(b) on one day within each quarter of the plan year under the quarterly testing option of 1.410(b)-8(a)(3), each of those four days is a testing day. Similarly, if a plan is required to satisfy section 410(b) on every day of the plan year under the daily testing option of 1.410(b)-8(a)(2), every day of the plan year is a testing day.