LaserWriter 12/640 PS: Paper Weight for Duplexer

The specifications in the LaserWriter 12/640 PS User's Guide for paper weight are confusing. The User's Guide, in a section about the duplexer, mentions 16-24lb paper is supported from the cassette and 16-32lb from the manual feed slot. The page listing the specifications of the LaserWriter lists 50lb paper through the manual feed slot.

Does the LaserWriter 12/640 PS printer support a different range of paper depending on where the paper is feed from? Also, does the duplexer support irregular paper sizes if my application does?
The LaserWriter 12/640 PS User's Guide is a little confusing. Here are the correct specifications for paper used with this printer.

Printer from paper cassette (either 250 or 500 sheet feeder): 16lb to 28lb

Printing Duplex: 16lb to 28lb

Printing from Multipurpose Try to optional Face Up Tray: 16lb to 50lb

Printing from Multipurpose Try to Face Down Tray: 16lb to 28lb

Duplexer Paper Size Support
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The duplexer supports letter, legal and A4 paper sizes. These sizes are supported by the engine and LaserWriter driver software. Any other sizes will likely cause jamming due to timeouts and handling problems.
Published Date: Feb 20, 2012