Would you believe me if I said I didn't know either? I've heard Muppets or Courtyard.
I know they've scoped out both locations for HS stuff, but I do not believe, especially after tidying up the theater, Muppets is at active risk.
Giving Courtyard 60/40 odds for the location. I don't believe they'll mess with Muppets until they set them up somewhere else in WDW. But I do think the clock will start ticking for them once Courtyard is solved.
Also someone who told me about Cars in FL also said Courtyard was being penned for a "Pixar-franchise land" so, hm.