I have already received my 2019 tax refund. I failed to include the Form 8962 but believe I should have. Should I file an amended return now or wait until I receive an IRS letter and then follow TurboTax posted guidance on how to reply?
You can wait until you receive the notice from the IRS. Please see the TurboTax FAQ: The IRS is requesting Form 8962 for 2019 for more information.