After you file

I filed an amended return for the tax year of 2018, mailing it on Aug. 10 (e-file not available for 2018). I've tried to check on the status using the IRS tool, and it's not even showing up as received. It's been more than 16 weeks. This thread is helpful in that others appear to be in the same boat. I also tried the phone line, but realized I would not be able to speak to a human. But I wonder if anyone else who mailed in an amended return in August has gotten any confirmation of at least receipt? I just wonder if they are opening the mail from then yet, or if there are still trailers full of unopened amended returns.