npub1a4cfqcj5cq9qauuzz33rqq63kudnu6k7x4fe4xep93s7lu5hgk3szqt2kf (npub1a4c…t2kf) I think this is a common obfuscation technique recommended by many people to avoid precisely naming your birth year, which many people still mistakenly believe is a modestly secret piece of information.
Certainly when I was a kid this was advice given to me.