I've added a new function in the "User CP" - "Profile"

Now you can set your own Time & Date preferences.

This is where you can change it:

On the bottom NavBar, all the way on the right side go to "User CP"

Then on the left side of the page, go to "Edit Profile"

Go to the bottom box "Aditional Information"
You should see the "Date Format" and "Time Format" Options