I don't know much about company history, but I have virtually the same bike - may have come out of the same shop since I lived in MA when I bought it from a friend in the 87-89 timeframe. I think the forum helped me date mine to '85. I've seen a few older models built with 531 as more of a sport-tourer, and this model with Aelle, plus someone posted a mid-late 80s MTB a few months ago.
Mine came with 600EX, Mavic bars/stem, and 600AX seatpost, rolling on Mavic Montilhery Route tubulars, . It started off the same light metallic blue, repainted darker blue in the early 90s, after an RD grenaded and took out the rear dropout. It has a random mix of components, mismatched wheels, etc from when I replaced things as they broke/wore out or I found deals.
I rebuilt it in basically 'as run ca. 1999' configuration a few years ago: