Our attention was drawn to this update by an X post of user Artem Russakovskii, and we have since verified it ourselves. The responses to the post suggest that this was a long-awaited feature for some users.
One reason that we hadn't spotted this change before is that Google made it with seemingly no form of announcement. It arrived with the latest Google Photos version 7.11 update on December 16, but the album signposting addition isn't mentioned in the Play Store description of the update, nor is there any mention of it on the Google Photos blog. It's almost as if Google was slightly embarrassed that the feature was missing in the first place.