More info found here, https://us.forums.blizzard.com/en/wow/t ... -29/181282
''That said, because of some of the issues that were encountered, we were not able to test other aspects that we’d planned for. As a result, we will be doing another stress test on Wednesday, May 29 from 2-4pm PDT. The stress test realm will become available at 2pm PDT and the level cap will be increased to 10. For access, we will be including everybody who was invited to the test on May 22. Similar to last time, the stress test realm will continue to be available until 4pm PDT on Thursday, May 30 so there is additional time to check out the starting experiences.''