These things tend to rotate. Sometimes there are less, or more. We have a Burley tandem that really belongs permanently in the basement ready for action just in case. They are all handbuilt, lugged-steel frames with the name of the individual who crafted the frame on the downtubes - straightforward, no cute names, no descriptive models, no brand names conjured by marketers - just who made the frame.
Be well, enjoy any Autumn weather that comes your way, Gunnar