Which amps? Solid state amps or valve amps?
The valve amps seem to be upgraded regularly - CAD-211C became 211AE and now 211FE. Same with the CAD-805C.
The solid state amps might be EOL'ed thanks to the end of a transistor run. Transistor manufacturers tend to make batches of these - if demand remains high, they will make more batches. But if a transistor does not sell well - once the batch sells out, that's it. You can't get any more. Cary might have run out of stock of a particular transistor, forcing a redesign and thus a new model.
The valve amps seem to be upgraded regularly - CAD-211C became 211AE and now 211FE. Same with the CAD-805C.
The solid state amps might be EOL'ed thanks to the end of a transistor run. Transistor manufacturers tend to make batches of these - if demand remains high, they will make more batches. But if a transistor does not sell well - once the batch sells out, that's it. You can't get any more. Cary might have run out of stock of a particular transistor, forcing a redesign and thus a new model.