As someone who takes the MBTA's Fitchburg Line every day, I can say that I haven't seen any tankers at Veryfine/Kraft in close to two years- long before the rebuild project got underway from the Willows East. Not sure if Pan Am "lost" them as a customer or not, but the Veryfine's siding has been dormant for a long time. It is still connected though, so perhaps they will eventually come back as a customer.
While work on the Fitchburg Line now concentrated from Littleton East, there looks like there is still some work to be done around CPF-WL. Several bulldozers and empty signal shacks have been deposited there in the last couple of weeks. Also, before the Wachusetts Station is ready to come online, a turnout will have to be installed from the Fitchburg commuter platform stub track to #1 Track west of Fitchburg Station. That might present a service disruption to the PAS main for at least a weekend.