Press Ctrl + U once BEFORE the loading bar reaches 25% or 50%. I have found that the best time to do this is immediately after character selection, when the load screen pops up. I immediately press CTRL + U once before I see the progress bar even move.
If you fail to do it in time, ALT+Z and log out, go back to server selection, select character and try again. This has worked for me every single time.
Don't press Ctrl + U twice, don't press alt + z unless it fails.
Hope this helps at least a few of you.
Edit: I should note that if you fail to do it in time and press alt+z and nothing comes up, press ctrl + u one more time and try alt+z. What CTRL + U is doing is hiding your UI, pressing it twice brings it back (but screws up your quest tracking if you do this in game), so I imagine the problem relates to loading your UI, and that press CTRL + U before it gets loaded is causing a refresh.