Okay - this is what I have, and hopefully this data helps. The dates are to be viewed skeptically - but there are some observable trends and I agree with Michael/Amberg that Allegro serial numbers do appear to be sequential. At any rate, you get a list in serial number, description, what I believe the model designation to be, notes on frame details and parts, and links to the assorted bikes as they appear online. Have fun!

Please be advised that the document linked above is a Google sheet, etc.