I've been checking weekly to see if there has been an update, and finally this week I at least found out that the IRS has, in fact, received my amended 2018 return. Here's the message I see when I log into www4.irs.gov/wmar (wmar is the "where's my amended return" subsite):
"Your amended return was received on August 03, 2020. However, it has not been processed. We apologize for any inconvenience.
Please call [phone number removed], extension 623, between the hours of 7 a.m. and 7 p.m., Monday through Friday. You will need a copy of your amended return.
Hope this gives others hope.
