This can happen for other modes as well, like I have seen it in pretty much every mode that has a leaderboard before, particularly FFA and maze. So that's why I was wondering about those as it makes it possible to complete the leaderboard and 1st place as soon as you spawn.

In theory, it is possible to complete these in under one second which can occur if no one else is in the game. Are there any rules against submitting the time in that situation?