Oh billing :( My own disappointing incident was metering customer usage in Bytes when billing was setup for Gigabytes. A couple of “concerned” customers noticed that super quick when the new functionality was turned on. Having to sort that out at 3am highlighted how many “business process” dependencies dont have the same level of operational response as our systems. On the plus side it highlighted some areas to improve continuous monitoring (and alerting) of what customers are metered and billed.