Big Sur Browser agent

So far, in all the Big Sur beta's I have seen, including 11.0.1 Beta (20B5022a), Safari identifies itself (HTTPUserAgent) as: Mozilla/5.0 (Macintosh; Intel Mac OS X 10156) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.1 Safari/605.1.15
Why is it still identifying as 10156 instead of either 1016 or 11 ?
Big Sur Browser agent
 
 
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