I have seen plenty of people upload games they've been making for months and had no relation to the theme of the jam. I guess those games will not get included in top places etc
If u do it then they don't gonna even know but remember game jam test your skill in a limit amount of time, if you do that then you can't know if you're good at time management, etc.
Usually the rules say you can鈥檛 do this, but it doesn鈥檛 look like it鈥檚 in the rules. I could be missing it though.
When it is against the rules, we have to report it to the host/organizer DIRECTLY. I made the mistake of reporting it to itch, but itch doesn鈥檛 let the organizer know.