+ AA6YQ comment below
I have now confirmed that uploading my QSOs to LoTW now works! I am a very happy camper. There is a very slight delay but nothing serious.
+ QSOs submitted to LoTW are placed in a queue that is processed in arrival order by the LoTW Server. The ARRL maintains a web page that shows the expected processing delay at the beginning of the most recent hour, and at the beginning of the 11 preceding hours:
+ On the QSL tab of DXKeeper's Main window with the "QSL Via" panel set to LoTW, clicking the "Check LoTW Queue" button will display the expected processing delay as of the beginning of the most recent hour.
+ Generally, this delay is about 1 minute, but it can increase substantially when a log containing hundreds of thousands of QSOs is submitted to LoTW. Immediately after a contest, the expected processing delay is often denominated in hours.