They were actively working on the facade all day today and there was air blowing out of one of the AC vents so they must be working inside too.
Unless they finish really quick, I'm expecting for the queue to be similar to Orlando (enter Gru's house, go to covered-but-lightly-themed video screen switchbacks behind the neighbor's houses, reenter Gru's house with the glasses pre show). So while the queue won't be entirely indoors, it will at least be covered.
Team member said something about a May opening (most likely for the public with softs coming in April like Transformers).