10m WSPR - USA spots today

My 500mW 10m WSPR-AXE-CW beacon was again being copied in the USA today by several stations. I think something odd was happening yesterday. K9AN (6505km) copied me first at 1406 and he was again the last to copy me at 1600z. The USA opening here was less than 2 hours.

UPDATE 1805z:  I spoke too soon!  At 1756z I was being copied by K4COD (6826km). The 10m band is still open to the USA.

UPDATE 1840z:  No further spots since 1756z. Often the longest distances occur just before the band closes.  K4COD gave me a report of -11dB S/N, which was very strong for 500mW.