This is the newest block 5A render. This parcel contains a 155 room boutique hotel on the lower floors with 117 condo units above it.
In the old rendering, the box is could've possibly been the as-yet released building on Block 5B, but now the box is clearly over the parking lot and buildings of Assembly Square Marketplace on the other side of Grand Union Boulevard. Is this the grey looming box of imminent domain?
View from Apple Maps. You're sure it's not 5B? Remember the renders show a small road between the two buildings from this
Looks like an limited service hotel (Marriott Fairfield/Res Inn, Hilton Garden Inn, etc.) on four floors, based on the presence of a breakfast room and no restaurant.
It appears 5A/5B are nearest to the orange line and swapped from the original plans with block 6. If you look at the plans, there is no outdoor bar that is presently there. Also reached out to federal realty and the condos are opening in 2017 so it appears they swapped blocks 5 and 6.
5b is where the beer garden is, which is staying for now. 5a is where they are putting the hotel/condos that just started driving sheet piles. Block 6 is where they are putting the tall tower and parking garage I've been posting pictures of, across Canal St from AVA closest to the main Orange Line entrance. Block 5 is basically across from K-Mart.
From today; a panorama of Block 6 with Block 5A construction off to the right:
Corner of Revolution Drive and Grand Union Blvd: