BAR bus service

Please excuse if off-topic for non rail service, but if a bus subsidiary of a railroad company is considered to be on-topic, I have a question.

In the 1970's I understand that the BAR bus service ran through to New York via Greyhound.

At what point did the BAR and Greyhound have the junction point and did this also have a Maine Central/B&M bus service component as well in between. What was the arrangement, was it "pool" service or end-to-end? Did the buses physically run through and/or the drivers? Did the buses alternate on different days for BAR and Greyhound, or did one company or the other do the full honors?

What was the scedule of that route, and is a scan of the timetable available to view? Any other service information on this through routing?

Finally, given that most of the Trailways bus companies originally had railroad subsidiary bus services as their original routes, why did BAR select Greyhound rather than Trailways to use in their through bus service?

Thanks,

Vytautas B. Radzivanas
Perth, Western Australia

Just want to say one thing. I'm pretty sure the Bangor and Aroostook bus operation was not a subsidiary, like Boston & Maine Transportation Co., Maine Central Transportation Co. and New England Transportation (NYNH & H RR). I think it was operated directly as a part of the railroad as the Highway Division and was an integral part of the railroad.
Whatever through arrangement to faraway places BAR had, I know not. BAR's bus operation outlasted its passenger trains by about 20 or so years.

B&A bus service interchanged with Greyhound in Bangor. You could buy a ticket from a B&A agent to any destination serviced by Greyhound and Greyhound also honored B&A bus passes.

Heading home for winter break while in college, I rode a BAR bus from Bangor to Boston. December 1975. The BAR pooled buses with Greyhound. We left from the Bangor House Hotel about 5pm and arrived at the old Greyhound Terminal between St James Ave and Stuart Street 6 hours later.