In our continual, internal Sandbox QA testing, we've recently noted errors where certain Labs fail to provision correctly. This is characterized by a lab failing to complete the Lab's provisioning "Setup" command - sending the Lab immediately into a "Teardown" mode. So in essence the Lab never becomes available.
Our current recommendation is that if you encounter this error, simply re-initiate your reservation.
We are working on resolving this issue with the utmost urgency, and anticipate a fix shortly.
Any updates regarding this issue will be posted to this thread.
We sincerely apologize for any inconvenience this issue may cause.