@peter that's ok because the goal isn't to make money and I have no idea if a short is the correct way to do it. Maybe it would be best to grab as much action as possible 24h before the report and dump it all when the report is release / 30 minutes before market close.

Maybe technic similar to SEO bombing could cause automated trading machine to make it dump and pump the following day but that sound very risky, I wouldn't want to be caught doing that