Those always happen at midnight, whatever local time is legally in effect where you go to do your first legal drinking, so there are no scenarios in which it would have any more effect than robbing you of an hour to get plastered in public. Although, if you live just on the right side of the right time-change border, and your birthday is on the right day, and the laws on either side of the border are just right, you might be able to manage as much as 2 extra hours of drinking.
I had always heard (but it may be urban legend) that trains have to stop for 1 hour when switching back to standard time due to a legal requirement of their timetable. If true, it is the closest I can get to the OP’s question.
Quite untrue. It costs the railroad real money when a train is stopped, and they would certainly not do it for a silly reason like this.
In fact, the standard time zones that we are adjusting time in were originally set up by the railroads. And one of their purposes was to make sure that their schedules were not messed up by various local time standards.