DS definitely began its run in Boston in April of '76 - and the reason why I'm certain of that is not only because I watched it, but because I have a full page ad from Weekly Variety that Worldvision placed about it just starting its run in Boston, and it's dated Wednesday, April 14, 1976.
Wow - I'd forgotten all about the Providence Journal's article - though I probably have it around here somewhere.
And you're right about Channel 9 - I'd forgotten about that, too. Channel 9 (WMUR-TV) was out of Manchester, NH, and even on a good day I was barely able to bring it in. DS was on Monday through Friday at 4:30pm (at least according to the TV Guides I just checked.) (Yes, I still have TV Guides from back then.
).
And I went to high school with a Jeff Arsenault who lived in RI and who was active in fandom. Could that be who you're referring to? Wow, I haven't been in touch with him in years and years and years. But I remember how I found out he was a DS fan like it was yesterday: we had gym class together, and one day I saw a copy of Barnabas, Quentin and the Frightened Bride on the top of his books as they were sitting on a bench in the locker room.
After the Channel 56 run ended, I didn't get to see DS in syndication again until I discovered in '85 that WCVX- TV58 from Vineyard Haven/Hyannis, MA had begun running it. In fact, that discovery was the very reason I bought my first VCR.