From the Boston Globe:
Dish Network drops CSNNE, Celtics' broadcast home
Dish Network drops CSNNE, Celtics' broadcast home
Dish Network dropped Comcast SportsNet New England — the television home of the Celtics, as well as numerous other programs — Wednesday morning after ending negotiations on a carrier extension.
The contract expired June 30, but the sides agreed on a month-long extension through July and then two 24-hour extensions in August before Dish Network pulled the plug.