At present, here are the known Wrath of the Lich King Classic release times in most major regions:
3:00 p.m PDT (September 26)
6:00 p.m EDT (September 26)
12:00 a.m. CEST (September 27)
6:00 a.m. CST (September 27)
7:00 a.m. KST (Septemer 27)
8:00 a.m. AEST (September 27)
If you’d prefer to look at a map of all the currently scheduled launch times, there happens to be one of those available as well:

As you can see, some countries will technically be able to access WoTLK Classic starting on September 26, but that’s only to ensure that those regions’ launch times match the assigned global launch time. In other words, no region will technically be able to access the game ahead of any other region, so there’s no point in trying to play with your profile setting to jump the queues.
Speaking of queues, you should expect the WoTLK Classic launch to be a bit…hectic. While nothing will match the insanity of WoW Classic‘s launch, anyone looking to jump into the expansion as soon as possible should expect to encounter some wait times as well as quite a few other players all trying to complete similar early objectives. Of course, history tells us that you should also probably expect minor launch time delays due to either server queues or backend issues. It’s best to be ready to go as close to launch time as possible, but it will take a minor miracle to ensure that even the majority of WoTLK Classic players are able to start playing the game at the exact moment it is scheduled to be released.
Still, many Classic players will no doubt be willing to wait at least a few minutes longer to jump into this expansion. As mentioned above, WoTLK really was a special moment in WoW history. While nostalgia is obviously a factor in every Classic update, WoTLK‘s status as the best expansion in WoW history isn’t entirely due to romanticized memories. The expansion’s zones, quests, classes, raids, and new/improved mechanics all hit a sweet spot that many players argue even modern WoW expansions have struggled to match.