Drafts of your report are automatically saved as you create them. If you accidentally close your browser or navigate to a different page, your latest progress will be saved as a draft. To permanently save the report, click on the X in the top right.
Returning to your opponents' page, you'll see your saved report under the Scouts tab. Clicking on the saved report will open it back up to continue editing.
The 'Duplicate Report' creates a copy of the report. This is best used when you are playing the same team more than once. You can open your report from the first game, and click 'Duplicate Report' to copy the report for your second game against the same opponent.