EPCRS - Small Excess Amounts

For 2020, the Owner received $ 150 above the match formula.

We are being told that since it is less than the $250 EPCRS  allows the excess to remain in the account. In other words, the   the Plan Sponsor does not need to forfeiture the  excess amount. 

The question is,  does the $150 remain in the account and then used to offset the 2021 match?  Or does the owner get the benefit of the excess contribution for 2020.

I am trying to wrap my head around the fact the owner is receiving an allocation higher than the NHCEs.   If the excess is used to offset the 2021 contribution  I could understand leaving the money in the account.   Having to remember to track the excess as an advance for 2021 could be a  nightmare.

It CAN stay in the account, but doesn't HAVE to.

I'd just correct it.