Manassas Regional Airport Frequency

I stopped by the Manassas Regional Airport yesterday afternoon. I only found one non-aviation frequency in use: 464.6000 [ d423]. This was used by a Fixed Base Operator (FBO) at the airport, but I was unable to confirm if it was Volo Aviation or Dulles Aviation.

Volo recently licensed five UHF simplex frequencies, but I didn't hear anything on them.