In that forum blog, I am curious why no comments are wondering if some app/process/task is REFUSING to shut down/sleep, and why no suggestions of getting a snap shot of task-manager screens at critical points is ignored. I am guessing the update changed some condition for some app/process/task that is refusing to give up control no matter what the sleep/hibernate settings are.
HangnJudge’s link has good advice on making sure your video driver is up to date/ not corrupted. There’s also a suggestion to update BIOS, which you can do via your hardware mfg’s updater (my HP has “HP Support Assistant” that can check on BIOS).