I just started playing again 2 days ago, but Grim-Batol EU is a nightmare when it comes to instances. First night, i tried several hours without getting in, (Was watching a movie on my second screen meanwhile). I even tried 04.30 in the middle of the night, but couldn't get it...and last night it was just as hopeless.

Hopefully our extended (14 hours!!) maintenance which they are doing now, will help.