MBTA issues draft RfP for Green Line extension; final RfP in May 2017 March 17, 2017 | North America News The Massachusetts Bay Transport Authority (MBTA) has released a draft request for proposal (RfP) for the Boston Green Line extension. The draft includes an affordability limit of USD1.319 billion, bas... This content is available to only subscribers. Username or E-mail Password Remember Me Forgot Password