I don't think that's true. The IRS put out a notice earlier this year saying that you had a postponement to 7/15(or 17 because of the Saturday), but if you filed after 4/15, you still needed to file 3 years after the original. So if you filed on 6/22/2020, then you would need to amend by 6/22/2023. So it was like an extension and not a change of the official date.
