I do not think the change was meant to be temporary. Rather, it was meant to prevent worlds getting overly congested as a result of DC travel or world visit. It's actually important for them to do it for server security.

You can probably get onto them at more quiet hours. Which of course, you may not be available then yourself - that's the very reason they are quiet hours. But if you really want to get onto a specific world you could set your alarm for the middle of night, switch, then stay logged in for as long as you can.