Amended Return - Electronic Submission v. US Mail

I amended my son's 2022 return that was electronically filed and accepted in January.  The software was updated today to allow me to complete the amended return.  The amended return reported additional capital losses that were missed in the initial return.  There was no change to the Federal tax due/refundable, but there was an adjustment to the loss to be carried forward.  The CA return reduced the tax due for 2022 (which was already collected by the FTB) by $12 - so he is due a refund of $12 from CA.  Here's my concern/question:

 

TurboTax indicated that the Federal Return needed to be mailed, but that the CA return could be filed electronically.  When I moved forward, TurboTax allowed me to file BOTH returns electronically and both returns were accepted.  Is the electronically-filed amended Federal Return going to cause a problem? I'm wondering if the IRS will treat the amended return as a second filing, which will really make a mess.  Further, do I need to mail the Federal Amended Return anyway, as the IRS may discard/ignore the second electronic filing, and the PDF copy of the Federal Amended Return has instructions for processing/sending the Amended Federal Return?

 

Thanks!