Hi Paul
It’s not so much the maximum number of QSOs but on the size of the file – from memory, that is 2GB
However, depending on how complex the QSOs are, and whatever else if going on on the server, upload and processing may exceed server time-limits – when you get a 500 or 503 error
We have a lot of logs with 10,000+ QSOs, so that sort of number shouldn’t be a problem
How big are you thinking?