He can produce such info, because it doesn't exist IMO, and in any case it's not accessible. It's a figment of his wild imagination, with no basis in sound reasoning. The "study" that he refers to is highly questionable, based on an average for an unknown population. His seven months average is like saying "the average wait at the DMV is five minutes". It's ignoring the more publicized timeframe of 12 to 18 months - and that it depends on complexity and examiner availability (Do they take vacations? Did they have a new birth in the family? Did he get sick, have an operation, get called for jury duty?).

And this indicates why people should never state opinions as if they were facts. I'd bet that if he'd said "IMO", you wouldn't have asked this question.

JMHOs,

SGE