The title is pretty self-explanatory, but the F2P is only for 72 hours (until June 24th, assumingly 11:59 PDT or EU equivalent), and only the base/battlechest version of the game (e.g. Warlords of Draenor) is give "for free." If an account already has Legion applied to it, then obviously you can still play that content for free, but they're not giving away Legion at this time, as it isn't part of the battlechest until BFA pre-patch drops on live servers.
https://welcomeback.worldofwarcraft....-us/index.html
http://www.wowhead.com/news=285075/w...-blizzard-shop
https://www.mmo-champion.com/content...e-Back-Weekend
Connect With Us