deskthority

I just started getting into the hobby and ran across this broken M2 that I am going to repair but upon disassembly I noticed that it had what looks like two manufacturing stickers on the back. At first I thought maybe the board had been sent in when the board was under warranty and perhaps it was refurbished but I'm not so sure. The date on the bottom sticker appears to be 24 September 1992 which is only the day before the sticker on top. I tried searching for something similar on other Model Ms or M2s but didn't find anything. I'm just the curious type and would really like to know why this might be. If any of you might be able to shed light on this I would greatly appreciate it.

Production error. Was probably damaged or nonfunctional and they sent it back through the production line. I have a 1987 Model M 1390131 with 2 back stickers one day apart, with large initials "JB" scribbled over both.