After you file

Unless there is a particular reason to file MFS...then don't.

You will have to amend anyhow to add in those missing W-2 forms.  Lesson learned?  NEVER file until you have everything in-hand...never !
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You have to wait...because the actual final paper forms will not be ready in TTX until after 2 Feb.  You also need to wait until your original refund is issued...that cannot be stopped  (or until after you have paid the IRS if you owed them)

.....waiting until at least 1 March is also a good idea, a number of other forms are coming out during February...and there may be a few more items you need to enter in your amendment.

Amending once is a bit difficult.......amending twice is a nightmare.  Just wait and do it once.
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But re-read what Carl posted below. That's pretty comprehensive.