Driver signature consideration for XP and Vista+

HCK8.0 will retire on Nov. 30. But HCK8.1 doesn't support Vista and XP test, what should I do for XP and Vista driver signature?

1. If the driver package is uniform, refer to the following HCK newsletter:

https://msdn.microsoft.com/en-us/windows/hardware/dn320463

Digital signatures available for legacy operating systems in the new Windows HCK for
Windows 8.1

When you successfully complete testing for a client certification of Windows 7, Windows 8, or Windows 8.1, use the Dashboard to create a submission package for uploading - the same process that you’ve used in the past. And, if you’re using a uniform driver that’s properly decorated to include Windows Vista and Windows XP, the dashboard has check boxes for free digital signatures.

2. If the driver package is not uniform. You can run xp and vista test with WLK1.6, and send the submission to sysdev with a special method. Contact sysdev@microsoft.com for the special method details