"I thought it was older SNs, but not so."
I tried a brand new, 2018, iPad 6 SN, and still get the message.
Perhaps how I came to this discussion group might help...
I did a search, and found this article: Identify your MacBook Pro model - Apple Support.
In the "Helpful? Yes/No" at the bottom of that page, I clicked on NO, and had the opportunity to leave Apple a message about it and how it could be more helpful.
I then saw a place to start a Discussion from that article, and when I tried, it stopped me with this message: "We're unable to find the community associated with the article HT201300. Please select a community below."
I then started this discussion from the choice of community that best-fit, but not really. So this could have made my question or at the minimum, left a gap in my question.
The web site does indeed work, but you can no longer search by serial number, as in the past. I'm not sure what it used to say, but now it says, "Browse Tech Specs By Product." Perhaps it used to say something else, although I'm pretty sure you could put other info in there beside just SN, so I don't think it was restricted to that.
I just miss the page because it would take you right to the product. I now need to go to one web site to get the product info from the Serial Number, and if that web site doesn't have all the information I need, I can go to Apple's page to get more details. Just an extra step.
Apple also has the following site: Check Your Service and Support Coverage - Apple Support, (which is the screen shot your left) which looks up by SN, and I had hoped it might give me more info, but it is very limited when the item is older.
Hope this clarifies better, or maybe it just makes my question more confusing!
Thank you, Allan, for your response.