The 48 Boylston St project is just a little 5-story building that will wrap around the existing Union building. It was approved back in 2015.
BDPA info:
http://www.bostonplans.org/projects/development-projects/48-boylston-street
Small project review submittal:
http://www.bostonplans.org/getattachment/9d984973-498e-4bc0-a0e4-60528305ab28
Unit Type - Square Footage - Number of Units
Studio/ 1 Bath - 502 - 36
1 Bedroom/ 1 Bath - 652 - 10
Commercial/Retail - 3,826 - 1 or 2
Office - 9,070 - 1