In 1886, after months of planning and preparation, all of the broad gauge southern track was changed to standard gauge in just thirty-six hours: tens of thousands of workers pulled up one rail of the track, moved it a few inches closer to the other, and spiked it into its new position. Railcars got new undercarriages, and the two separate smaller networks became a single, fully interconnected, national network.
Talk about a coordinated rollout strategy for a release date.