without getting too much into the weeds, i suspect you just need to make sure you submit your observations sooner than later when using the web uploader. if the page works like i suspect it does, then it uses a web token that is valid for 24 hours. so once the token expires, i'm guessing there's no good way to continue your session without refreshing the page. i'm not sure why the page asks for a name and password since i doubt you'd be able to use the page to submit the pending observations without a valid token. really, if the page works the way i think it does, then it should just tell you that the session has expired and force you to go to the login page to log in again (which would force you leave the upload page and come back later to re-input your observations).
EDIT: apparently, you should be able to resume your work…
… so if that’s the case, then something just needs to be fixed, and this bug report should probably be consolidated with the other one noted above.