I think you can count on the whole amended 1040 being e-filed with the 1040X form.
Back when it was only accepted via paper-filing, the IRS wouldn't accept just the 1040-X form, they wanted the whole as amended return.
Therefore, I'd presume IRS and Lacerte would have set it up to e-file the whole thing.
You don't need to "attach" the amended 1040 as a separate PDF when you e-file.
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