As a Googler privy to the internal postmortem: as stated in the public postmortem, all traffic was unaffected within 33 minutes of the problem appearing. The bug was very on/off: at 09:35PT a corrupted configuration stopped ~immediately (usually double digit seconds of propagation delay) all traffic. At 10:08PT it was verified that the whole service is running the configuration from before the corruption.

The >1h duration was for inability to change your load balancing configuration.