Many older relays seem suddenly less than 2 weeks old...

Just discovered, that my at least 8+ years old (since 2015-04-15 23:00:00) relay is labeled as "This relay appears to be less than 2 weeks old" in https://metrics.torproject.org/rs.html

Clicked thru few of these relays, same story with all of them. Some show last-restart date that is older than first-seen date...