"It takes 24 hours" is a clear sign that it's a human being looking up an internal documentation page and running the scripts it points to.
Unless I'm just not creative enough to reason why you can log into twitter from a country you've never been to with no 24 hour verification wait but fulfilling legal obligations takes 24 hours.
In their defense, if the backup requires accessing archive tape drive records, long processing queues in non-scalable systems, etc - this could easily take 24 "physical" hours of things getting lined up correctly.
It's one thing to show you the last 24hr of tweets. Another to get a complete twitter history for given uid.
Unless I'm just not creative enough to reason why you can log into twitter from a country you've never been to with no 24 hour verification wait but fulfilling legal obligations takes 24 hours.