After you file

Ok, so I can amend it right now? I don't need to wait for the IRS to process it?

The reason I ask is,
From a customer post in this forum, under "amend my tax return for this year" by jester6453, this is in the answer,

" If the IRS accepts your return, however, then you have to **wait longer until it has been fully processed** and you have received your refund.  THEN you can prepare an amended tax return and mail it in."