contribution for partial plan termination - retesting?

[M Norton]

It was determined (after year-end) that a large traditional 401(k) plan had a partial plan termination in 2018.  The plan operates on the calendar year.  Additional match contributions (plus earnings) were calculated and deposited to the plan in late 2019 as a correction for the 2018 partial termination. 

The plan administrator had originally calculated refunds to HCEs for failed ADP/ACP.  Now the PA is saying that the plan had to be re-tested  for the 2018 plan year after the correction for the partial plan termination, and additional refunds are due to the HCEs. 

Should the compliance testing for 2018 be re-run as a result of the corrective actions taken for the partial plan termination?

Thanks!

[Kevin C]

I'm having trouble seeing how a correction for a late discovered partial plan termination could result in additional matching contributions.  I can see reduced matching contributions if the reallocation correction method is used to correct an improper forfeiture resulting from a late identified partial plan term.  And, I can see the correction of a 410(b) failure resulting in additional matching contributions.  What exactly is being corrected that results in the additional 2018 matching contributions?

Your question about re-running the ADP/ACP test can't be answered without details about the correction being made. In some cases, corrections are done after ADP/ACP failures are corrected and the ADP/ACP tests don't need to be re-done. (for example, Rev. Proc. 2019-19 Appendix A .05(2)(g)).