Since 15:46 UTC today the wsprnet.org server is returning: 'Duplicate entry '2147483647' for key 'PRIMARY'' for upload requests
The number 2,147,483,647 (or hexadecimal 7FFFFFFF16) is the maximum positive value for a 32-bit signed binary integer in computing
So it appears that some value internal to the server is overflowing.
It is still failing almost 4 hours later