Currently for tournaments, top players who submit their final code early put themselves at a disadvantage as their code and strategy becomes available for opponents to test and optimize against. This makes the best approach waiting until the last minute to submit your final code.
Unfortunately, that can be difficult for people who have to stay up late to do so, or maybe even impossible for people in some timezones (for example if someone is in school at that time).
To avoid this problem, one possible way could be to have a 24-hour final submission window, during which simulations, rankings, and opponent code available for testing are frozen. So you can submit your final code anytime during this window, and it is not revealed to other players.
Not sure how hard the changes to make this happen would be on the CodeCombat side, especiallly freezing the code versions available to opponents. If the opponent code in the “Battle” urls points to a unique version, then it might be okay to just freeze the tournament landing page. If the url always points to the latest version of the player’s code, then it would be a bit harder.