Board Thread:Unanswered Questions/@comment-3522837-20150609063707/@comment-10993019-20150610231238

It's worth mentioning that (at least in AC5) none of the aces appear in the first playthrough, only when you come back to them on free mission. So they're more than likely non-canon. About Yellow appearing in the tunnel in mission 27, it's probably just an easter egg.