We are getting limited by the quota. As the documentation says, quotas can be temporarily exceeded and in our tests we could fetch about 3000 messages in those

We are getting limited by the quota. As the documentation says, quotas can be temporarily exceeded and in our tests we could fetch about 3000 messages in those bursts. After that, we would be 403'd for one to two minutes before requests would succeed again with quotas strictly enforced for an unknown amount of time past that.