These three arrived yesterday. A Premier, a Jeunet, and a Centurion (I think it was a Sport DLX, definitely not an IM).
The Jeunet looked like a late 60s bike, and had full simplex drivetrain (including an undamaged Simplex FD). I don't know if it helps with dating, but it had stamped dropouts.
All 3 are slated to be stripped and the frames scrapped.