Do I need to restate the DB plan?

Hypothetical question.

Law/IRS says as long as the account is cleared prior to 3/31/2025, you do not need to restate the DB plan (required amendments aside).

Plan DOT 12/31/2024, all assets distributed by 2/28/2025.

On 4/2/2025, a dividend shows up in the account, amount not relevant. Rolled out sometime in April/May - not informed timely.

Is restatement now required?

I think a public flogging of the financial advisor would be appropriate. 
 

This kind of stuff just frosts my behind. 

Happens to all of us but possibility of reality is there.

Sometimes, it is not the financial advisor's fault that unexpected dividends pop-up.

Still do not know what needs to be done?

FAs can completely freeze accounts so no dividends or interest hits the account. I don’t know how it’s done but I know it can be done. 
 

So get them to acknowledge they’ve done it and explain the costs of an additional report, filing, and 1099s have to be done.  

Thank you, interesting concepts of freezing the dividends. I will discuss with them.

All the best

First, there is no requirement to restate regardless. The requirement is that the plan was up to date with the law as of the plan termination date. If you (and/or the plan sponsor) are comfortable that the plan in its current form including all amendments is compliant, then there is no need for further action. That would be the case if you didn't even distribute assets until next year, like if you submitted to IRS for a determination letter on the termination and were waiting for such before distributing. 

It may have been advisable to restate back in December to ensure nothing compliance-wise was missed, but it wasn't required, either then or now.