Similar to Star Tours, I'd expect the timeline to be ambiguous enough to be able to please all Star Wars fans and not feel like it's too rooted in the current trilogy vs previous ones. There's also a whole new trilogy coming after this one too, so I think Batuu will feel similar but remote enough that it could live within any of the movies.
BTW, I just read the description on StarWars.com for Batuu and doesn't it sound A LOT like a sci-fi Radiator Springs?? Interesting...
http://www.starwars.com/databank/batuu
"A remote outpost on the galaxy's edge, Batuu was once a busy crossroads in the days prior to lightspeed. With the rise of hyperspace travel, however, the world -- notable for the lush trees and mountain spikes that decorate its surface -- was left behind, its prominence lost to planets on more popular trade routes. Today, Batuu is home to those who prefer to stay out of the mainstream, and a thriving port for smugglers, rogue traders, and adventurers traveling between the frontier and uncharted space. Significantly, it has also become a safe haven for those looking to avoid the attention of the First Order."