I am using the latest UEFI 1.14 and sometimes when I boot the laptop there is no "Press Enter to interrrupt normal Start- Up" message so I cannot access UEFI. So when pressing the Enter or F1 keys nothing happens. When I restart it usually works, also sometimes with a cold boot. It seems to be pretty random. This happened when I was on UEFI 1.13.
By default, Win8.1 shutdown is not a "real" shutdown. Instead it is a a hybrid-style shutdown that is somewhat like hibernation. From this state, after you turn on the computer you will not be allowed to interrupt the startup.
You can only interrupt the startup from a full shutdown, or during a restart.
Here is some more info about Fast Startup and how to disable it, if you want to try that.