After you file

*** UPDATE ***
I checked the IRS website again today and viola! it now shows that it was received on January 25th, which is actually the Monday after the Post Office delivered it on Friday, January 22nd.  I'm not sure why it just now updated as I have been checking it a couple times a week for several weeks, but hey, at least they acknowledged they received it!

So, for those that run across this post in the same situation I am in - looking for some remnant of hope that your amended return isn't floating around in the nether,  hang in there!  🙄  Although their site still says to give their system 3 weeks before shows up after you mail it, my experience is 3x what the site says as today marked 9 weeks from delivery (USPS) to showing up in the IRS' system.  Whoa!

...and that is just showing it has been received.  If I use the adjusted timeline and take the new multiplication factor (3x) and 16 weeks, 3 x 16 = 48 weeks total.  So, it could likely be Christmas of this year before I get the results of the amended return I mailed in January.