No surprises here, freighter "flow" eastbound is often daylight, so they going opposite the westbound passenger tracks. ATC can, I believe route them "opposing' as long as everyone is RVSM. A bit atypical, perhaps, because the tracks are based on the minimum time route, i.e. most advantageous winds, so usually they are separated by the wind factor. Light winds, etc. might be a factor.
GF