A CPA asked me to review a client's ADP testing. They left one TPA for another TPA in 2018. The plan passed testing in the past because it used the "Top Paid Group" election. The new TPA omitted the "Top Paid Group" election in the plan document starting in 2018 and elected to use prior testing year's results. For 2018, the plan passed since it was using 2017 testing results. March of this year, the TPA refunded ALL deferrals for 2019 stating the plan failed ADP testing and the client did not know the checks were being issued. The checks were just issued and sent out. There was no discussion regarding QNEC or anything else. This might be a stretch - but under EPCRS (Rev. Proc. 2019-19), Section 6.02, is it possible to change the method that was used to correct the testing for 2019? Stating the principal to keep money in the plan? We'd ask for all the refunded money returned and the client would put in the $2,759.71 QNEC to the one NHCE who did not defer based on testing not using the "Top Paid Group" election. That would be $69,000 put back in to restore the accounts and the HCEs keeping their tax savings. We are definitely changing the Plan to have safe harbor in 2020 & 2021 forward. No one ever explained Safe Harbor to them - they are interested.