A bugged flood occured (at sea, instead of land), movement points of ships of all factions decreased to a half. It is possibly gonna take many turns, until it goes away (cant say for certain, as there is a 1/6 random chance it happens every year, which is 2 or 4 turns in this HS I think).
But the moment it goes away (before Stark turn, as they are first in turn order), the factions sooner in turn order could use the restored mps to defeat fleets of players of players later in turn order, who didnt know its going to get restored, hence though their ships are safe... hence the rule
Well yea, though its not gonna be hurting your ships/men at sea, so you can move around just fine... as I said above, might take really long, so I suppose moving slower is better than not to move for half the HS![]()