The pre-expansion content patch, ending Warlords of Draenor as a relevant thing and beginning the pre-launch for Legion, hits the live servers on the 19th of this month. That's Tuesday. Fortunately, for me, I have only one thing left that I care about to do: wreck Brawler's Guild. I'm after the Follower exclusive to it (Meatball), and for my Death Knight it's the epic gem module that you have to go there to get it. I'm not that bothered about finishing it entirely, but for my main I'll go for it; for my alts, I stop at Meatball or the module.
So that means when Tuesday comes, all of the new versions of the classes and specializations will go live also. The time-limited pre-launch event will also begin on Tuesday, so the time to dust off neglected alts and level them to 100 will come. Why? The event drops very good gear that will let those alts leap into Legion content without worry of being pasted by it due to being too weak. It's also an introduction to how World Quests will work in Legion, so it's worth doing in any event.
Whatever you want to do in Warlords, do it now. Right now. It's done as of Tuesday, so get on it. Otherwise, see you in Legion.