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19:11
So you do know: The labels that your answer show from the kernel are mere suggestions to UDEV. UDEV might choose to set any name it finds useful and only if there is no rule to change the kernel label is it used to name a device and create the directory entry. Any idea that a major and minor number defines a label is incomplete (to say the least).
A perfect example of why labels (sdb in this question) are dynamic and connected to no particular kernel major or minor number. @StephenKitt

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