I haven't seen anything about Avengers on the Fantasy currently -- the Marvel characters seem to be on the Magic (Avengers Academy) and the Wonder (Super Hero Academy with Spiderman). But there's an empty three week block coming up on Fantasy's schedule that might indicate dry dock and refurb (April/May of 2017, but nothing has been announced yet.)
The Dream just recently got Star Wars in their Oceaneers Club, so I'd be expecting that in the Fantasy.