Source: Official Post
Blizzard
We’re going to keep the WoW Classic pre-launch test realms open and available for play through the weekend. Please feel free to test WoW Classic as much as you like.
The pre-launch test will end on Monday, August 12 at 9:00 a.m. PDT. We are not planning an in-game event for shutdown this time.
Thank you very much to everyone who came out and provided the testing we were hoping for! Thanks to you, we’ve been able to fine-tune our plans for launch, and we even captured a few issues that we were able to solve yesterday.
We’ll see you in Azeroth!
Source: Official Post