472kHz - lack of WSPR spots?

I was beginning to wonder why I was not getting spots on 472kHz WSPR.   At first, I thought it was just down to too few stations in range, until I noticed a "peer unreachable" message, so I was not synced to internet time, at least recently.   Having changed my internet time server and re-synced, I am now being spotted weakly by G3THQ (88km). The band does seem quiet though with very few UK stations active on 472kHz this evening. Perhaps those stations who are active are using different weak signal modes like OPERA?