Dec 22
22
Since April, Bing has been slowly testing a new BingBot user agent, slowly rolling it out to more percentages of crawls over the year. Fabrice Canel from Microsoft said while the new BingBot is still only doing 50% of all crawls, it will move to 100% of all crawls in early January.
Link:
Bing Will Fully Switch To The New BingBot User Agent In Early January