These reports can be found on Reddit and the MacRumors forum where some are claiming that the update would freeze halfway through the installation process. Some are claiming other issues such as failing internet connections despite being connected to WiFi, but whatever the case is Apple has deemed it to be big enough of a problem for them to temporarily pull it while they address it.
According to Apple, “Seed 1 of watchOS 5 is temporarily unavailable. We are investigating an issue that occurs while updating. If you’ve experienced any issues, please contact AppleCare.” What’s interesting is that most of the affected devices seem to be those who are using the Apple Watch Series 2, although given that Apple has since pulled the update we guess we won’t know if those on the Series 3 have been similarly affected as well.
No word on when the beta is expected to be made available again, but if you were planning on checking it out, we guess you have no choice but to wait, which hopefully won’t take too long.