Per Bulls.com: [updated: this appears to be a link they never published, but were prepared to]
October 26, 2009 -- The Chicago Bulls announced today that the team has waived guard Derrick Byars.
Byars (6-7, 220), appeared in eight games during the preseason with Chicago and averaged 5.8 ppg and 3.0 rpg in 16.5 mpg.
Chicago's roster now stands at 13.
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This appears to be a press release that they had ready to go that never was released. The official release shows that Byars is still on the roster.
When I saw this link originally on realgm, I thought that he was actually waived, but it appears to just be an unused press release someone found if I were to guess.
This is a speculative guess at this point, it's certainly possible he is really waived. However, I got a press release from Bulls PR saying he made the team and didn't get one saying he was cut.
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I just got the email from the Bulls PR department. Byars is officially waived. They probably just haven't fixed the date on this article yet. Sorry Mr. Happy, I wish I wasn't right on this one, and they kept him.
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Just some random speculation, but it appears they were ready to waive him on the 26th. They must have been pleased with him though and probably kept him a few extra days to throw him some cash. I don't know, could be wrong on that, but if not, kudos to Bulls management for extending him a bit to pay him something for his hard work.