[Chuck Schwark]

Cabinet manufacture dates are from the cabinet makers' shops (many), not the Philco factory mfr date of the chassis.
Chassis mfr dates correlate to the chassis serial numbers only, per the graphs on my site.
Also, over the years, cabinets become swapped with chassis' etc......
Philco could have easily kept a run of cabinetry on hand for many months before used by a factory run of models that used a particular cabinet type.

The various shops used by Philco are designated by number thusly:

Philco Model Shop - Plant 2
Philco cabinet factory (on premises)- Plant 8
Watsontown Furniture Co. - Plant 15 (later bought by Philco)
Mengel Body Co. - Plant 16
Smith Cabinet Co. - Plant 17
Wabash Cabinet Co. - Plant 18
Maddox Table Co. - Plant 19
Pooley Furniture Co., H.A. Prock Lumber Co. - Plant 20
Pennsylvania Furniture Co. - Plant 21
Red Lion Cabinet Co. - Plant 25

This number (just digits) may have been emnbossed on bottom or chalked inside the cabinet or elsewhere.