I suspect that the blue line has been erased by now. They use one at the London Marathon too, and it's erased within a day of the race. City authorities don't want a permanent line.
The blue line is NOT the measured line. It's out there simply as a guide to let the runners get ready for upcoming turns. The measured line is tighter at the corners than the blue line, which is laid down with a special painting truck.
How would you get a copy of the report? Good question.