10m tropo?

WSPRing on 10m this lunchtime I've been receiving G3JKV over a distance of 123kms. There is no sign of aircraft flutter on his signal, so I wonder if this is by tropo? He is, like me, only running QRP and this again illustrates how useful WSPR is at "winkling out" fleeting openings. I'll be swapping back to the 10m halo shortly.