I think I observed this first after 2.0.4. Never had a problem before.
I enter my eQSL credentials in my account settings under "Third party settings". I save the view and never touch that page again.

I'm doing eQSL imports and uploads.

Then suddenly, the next day or a few days later, I try to do an eQSL upload or download again and suddenly I get the message "You have not defined your eQSL.cc credentials!". It's a lie. I have provided them and it worked.

I go back to the account settings page under "Third party settings" and indeed both eQSL.fields show no data. They seem to have cleared. Why?

Is anyone else observing this behaviour?
In the meantime I'm running 2.0.7 and I'm still having this issue.