User talk:CI611

That very well could be it, however I am unable to find any reference to the letters being a locale. I do have a screenshot, but appears I'm not allowed to upload. — Preceding unsigned comment added by Lowlevel (talkcontribs) 23:42, 17 October 2022 (UTC)

Unfortunately I could not find any B1 version on the internet, however it is enough to explain the letters by this screenshot or Mac System Software AB-6.1 ←this page I guess... CI611 (talk) 00:20, 18 October 2022 (UTC)