My guess is they are 'end run'. It's common practice to build more than ordered to allow for some being defective. If you get a low level of defective, you have extra product. Was very common in Japanese guitars in the old days. You would see guitars with no name on the headstock, or a sticker over the original name.

Altec didn't waste much. These are likely extra from a run for WE, so just slap on the Altec sticker.