He wasn't at the last show in Mallboro and he had always been there in the past. His wife had wanted him to fully retire for some time. That's why he let his New Hampshire license go and move down to the Chelmsford shop.
Len, Terry was a always at The Holbrook shows, and didn't make the Nov '17 show nor is he scheduled for the March '18. as others have stated I believe he did close up shop, due to some Health issues, i don't know how bad or seriousness it was.
i am pretty sure, he is OK and like you say enjoying retirement, but yes for years terry and his crew were great to see at our show ( holbrook) if nothing else just to talk to.