You generally do not need to amend for Federal.
However, taxpayers would have to file an amended return if they did not originally claim the EITC or other credits, but now are eligible because the [unemployment comp] exclusion changed their income. These taxpayers may want to review their state tax returns as well.
See these re State:
If you already filed and didn't get the 10,200 unemployment exclusion you do not need to amend. The IRS will be adjusting it for you. See,