Re: Fastly 'fesses up'
"I notice they don't bother to mention what the 'customer configuration change' was. If I was cynical I might be inclined to think it was something so simple they'd be embarrassed by revealing it."
If that's the case, it could easily be any one or more of [missing|extra] [semi-colon|comma|space between parameters|line-continuation character], unquoted or otherwise not-properly-escaped string containing spaces or other special characters, etc, etc, etc.
With the best will in the world and trying to always get these details right, I'm sure most of us here have probably made that sort of typo/mistake at least once?