That isn't a voltage change where you'd use multiple transformers in sequence generally, let alone if it's at the same site for the main/primary feed. A redundant feed counts the same, just to be clear, it's more that some low-power/"control plane of the electrical switchyard" applications may use a lower voltage if conveniently available, even if that means a second transformation step from the generators/grid to the load.

That said, the existence of the 480V labeled intermediary does suggest they have a 277/480 V outside system, and a 120/208 V rack-side system.