i think its for anything membership package or ac package just check on design notes they have it up their i think early this week or last week. I havent used it but what i heard about it its pretty good
Before a war starts, yes there will be a legion only class. It depends what you mean though as Glacial Warlord can be bought with ACs, BUT there will also be a legion only variant available for Legion Tokens. If you want it, might want to start farming.