I haven't done this but I was in a situation where I might have considered it under slightly different circumstances.

There are 3 flights from AAA to BBB: 8 AM, noon, 4 PM. Pax is on the noon flight, and wants to fly at 8 AM. Unfortunately, Pax's fare class isn't available on that flight. Nor are RUC upgrades available on the noon flight.

Pax does an SDC to the 4 PM flight, applies a RUC (getting F), and then does SDC to the 8 AM flight using the enhanced ability to switch to any flight with available F.