Retro amendment to add last day rule on discretionary match

Plan has discretionary match but no allocation conditions (no last day rule).

Plan sponsor now considering making a 2020 discretionary match but wants to amend to add last day rule.

OK or a prohibited cutback for participants who deferred in 2020 but have terminated employment? 

Prohibited cut back to add a last day requirement for 2020 for anyone who statisfied the current allocation requirement.

2020 is out, nothing can be done. However make sure that they amend and execute the plan by 12/31/2020 for 2021 if they want to continue with the discretionary match and have last day rule and any other provisions. if the plan is not amended till 2021, 2021 will be out too.

Keep an eye out for coverage, too.