I'm very familiar with Ed Greenberg and Jack Reznicki's work. In fact I have in front of me here a copy of their book "The Photographer's Survival Manual, A Legal Guide for Photographers in the Digital Age," and I've seen them speak.
tspear posted a link to a PDF titled "Duration of Copyright." That doesn't actually talk about posted copyright notices, only about how long the copyright lasts. The correct PDF is "Copyright Notice"
https://www.copyright.gov/circs/circ03.pdf
...which says on the second page, under Form of Notice, that the date on a notice should be "The year of first
publication." Not creation.
We have to be careful here. There are three different copyright dates that this thread is talking about as if they have the same implications. They do not.
Date of creation: When the image was created. That is recorded by Camera EXIF. Your copyright of your image starts here, but that doesn't really affect the copyright notice or legal actions (see below). The only importance of this date is when it runs out, which is after we're dead, so we move on to the next two dates which have more immediate importance.
Date of publication: When the image was published. This is the year that goes on the copyright notice. If you're posting the image right away, then it's the same as the date of creation, but in many cases the date of publication could be a different year. Because this is the date that the Copyright Office says should be in the copyright notice, it probably should not be automatically bulk-tagged in Lightroom using the Date of Creation unless that really is the year you published every image on that card.
Date of registration: When the image was registered in with the US Copyright Office. Of course, this could be different than the first two dates, although the year might be the same. This date, along with the publication date, are what matter the most if you bring legal action against an infringer, because your lawyer needs to prove that registration occurred before infringement. This date does not go on the copyright notice.
So while we can all agree that we need to have accurate records of the date of creation and registration, we should keep in mind that those two dates are not the ones that go on the copyright notice. It is the date of publication that goes there.