If your returns were already accepted, you only need to wait for the 1040X form and instructions to be finalized.
You can double-check the IRS website to see if your forms have been accepted here:
<a rel="nofollow" target="_blank" href="
https://sa.www4.irs.gov/irfof/lang/en/irfofgetstatus.jsp">https://sa.www4.irs.gov/irfof/lang/en/irfo...>
Then, when you're ready you can check back here for how to amend (we should be ready in 2-3 more weeks): <a rel="nofollow" target="_blank" href="
https://ttlc.intuit.com/questions/3061514-how-do-i-amend-change-or-correct-a-2016-return-with-turbot...>
