The official FAQ for 878 Vikings wrote "Round' instead of "Active Faction's Turn" when describing unit movement.
Under: "LEADER PHASE F.A.Q." in the FAQ file.
Question: "May a leader move into a shire with a second leader and pick up units from the second leader's card?"
From Official FAQ in Files section.
Also note that units moved or dropped off by a Leader are not eligible to be added to an army without a Leader later in the round.
Should say: "later in the Active Faction's Turn."
Those units dropped off, in above example, by a Leader ARE ELIGIBLE to be added to an army without a leader on the other Viking Faction's turn in the same round, if second Viking faction hasn't yet played this round.
878 Vikings FAQ