User blog comment:MasterCharmander13/This....is actually interesting/@comment-25203403-20150808012406

Two theories: like the article says, it could have something to do with the Tenth Doctor's encounter with Caecillius. Or it could be vice versa, so that there's not only multiple Peter Capaldis throughout time, but there could be multiple David Tennants as well.

Or it's for the tenth anniversary.

Or maybe it's a coincidence...

I doubt it.