Primarily effecting HP devices, particularly those running the new 1809 version of Win10, some other [unspecified] PCs & laptops, running win10 1809 or the current 1803 version from April, 2018, are experiencing BSODs after the update, preventing win10 from running. For effected HP devices there's a way to get win10 running again -- the problem is a driver, HpqKbFiltr.sys, that has to be renamed [or I assume removed].
neowin[.]net/news/users-are-reporting-bsods-with-the-with-latest-patch-for-windows-10
windowscentral[.]com/fix-blue-screen-death-after-getting-october-patch-tuesday-windows-10