Q: Why is my bitlocker data drive unlocked for a few seconds after boot? To specify: why is the data on my bitlocker encrypted drive available for a few seconds after logging in? After a few seconds the system 'notices' the drives are bitlocker encrypted and need to be unlocked first by entering passwords. Why are the drives in an unlocked state for a few seconds?
These are aspects of the situation:
- I do not use auto-unlock.
- I have experienced this behaviour with a 128bit encrypted drive as well with a 256bit encrypted drive.
- Running Windows 8.1 Pro
- If I lock the drives before shutting down (manage-bde [...]), this does not happen. (But why should this be required?)
- Some fixed drives are mistakenly perceived as a Bitlocker on the Go Drive. (Removable)
- The system does not have a TPM chip.
- Opening Windows Explorer window and navigating within such a drive is sometimes possible if one is quick enough. The script however is quick enough.
Looking forward to any insight into this weird behaviour of my OS and bitlocker.
If anyone has a solution, besides manually locking the drives before shutdown, I am all ears!
Details: 
How I noticed:
I use a script launched when logging in that checks if a folder on a encrypted drive is available, if it is, it launches certains apps that require data on the drive, if it isn't available (because I haven't unlocked the drive) it waits. I noticed it sometimes launched apps before I got to unlocking the drive; I changed the script to open a txt located on the drive in notepad and voila: next reboot the txt file appeared just before the system 'realizes' the drives are bitlocker protected. Obviously I cannot edit and save the file in this stage anymore (though I expect the script could), but I don't expect nor want any files to be readable after logging in BEFORE I unlock the bitlocker protected drive.

A: The bitlocker service might not be active yet, thus the computer thinks that it is not locked. So when the service starts, the computer then will realise that the drive should be lock, thus the drive is then locked.
