The Searsport Branch has been 25 MPH since CMQ did a tie and surfacing job in the 2016/2017 timeframe. There had been a few 10 MPH restrictions towards the end of CMQ, but that was due to the crossing protection not working correctly. Currently from the south cautionary limits at NMJ to Dead River in Hampden there is a 10 MPH slow order due to the replacement of the I-95 overpasses as well as a few "rough" spots in the track where they have some drainage issues. CP also recently removed roughly half the yard tracks at the "farm" at NMJ which has made switching difficult.
Still getting used to seeing CP locos on the B&A... it's one thing to see them on the Moosehead but still strange to me.
CP started laying CWR down Van Horn and on towards the Village at Brownville in late 2021. We'll see if next year they keep going to NMJ (which I suspect they will), but I could see them when intermodal/auto/SJ traffic takes off further they add fully another train pair (142/143) St. Luc to Saint John and then change the current manifest back to 250/251 with making that new origin/destination NMJ.
Brownville Jct isn't going to get any bigger and will need fluidity to make it all work in the future... the ST traffic will someday go back to Keag, but for now it's going to be a mess as traffic grows. Also, F16 has had quite a few times big trains and left tonnage behind... a pair of GEs sadly would make it a much easier trip, and again just blocking at St Luc the ST(CSX)/NMJ/Searsport traffic would increase fluidity, even if it was a 5-day a week job.