All right, let’s start at the very beginning: Someone did not proofread the news post for Final Fantasy XI’s next boost campaign starting on May 11th, so it’s titled as celebrating the game’s “21th Vana’versary.” That should be “21st.” Fortunately, the rest of the numbers in the post are accurate, so if you were worried that you weren’t actually getting doubled experience and capacity points from chains when the event starts… no worries! It’s real, that’s a substantial boost, enjoy it.
Other boosts include doubled Bayld from reives, bonuses to Geas Fete rewards and item enhancements, an Adoulin reward dial for the mystery box, and various other improvements. It’s an anniversary campaign; you knew it was going to just offer a whole lot of stuff to turbo-charge your play experience. Just be sure to take advantage of it while it’s running; the campaign starts on May 11th but only lasts until May 31st.