THIS. Sorry if this was covered elsewhere in the thread, but tis exactly what I wanted to say. This requirement may have been stated elsewhere, but I feel the actions required to "complete" this season were significantly different from last season, and should have been more clearly stated.
Last time, basically all you had to do to get everything was reach level 100, which as a sub, I did with plenty of time to spare. I eventually noticed I still had to buy the last mount and customizations with GS tokens (lame, but I had them to spare): It wasn't until after I realized I was still one short that I realized about the rep requirement/achievement. I had PLENTY or syndicate plans, but not enough time: at full legendary now, but finished at 67535/70000. Holding on to syndicate plans/tokens seemed like a great way to earn conquest points for alts, so I wasn't in a rush to max the rep: Had I known I needed to, it wouldn't have been no problem