Hi,
Dgraph Cloud backends have max pending query limits set to prevent the backend from getting overloaded. This value is set to 16 for 1M backend which we believe is the right amount of concurrency a 1M backend can handle without running into resource limits. I have just updated it to 32 allowing for more concurrency during your Beta testing.
In production, you should pick a higher tier depending on the load you anticipate.
Please let me know if this resolves the issue.
Thanks