The game balance is completely different (no attack items, fewer racers, improved AI) and I've done a lot of art direction changes (TV effect, consistent vaporwave theme) so I'd prefer the term "remaster". And there's nothing in the jam rules that explicitly forbids it... in fact, here's an official statement from the Yoyogames staff running the event that says this was left in intentionally.
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The term "remaster" is definitely more applicable here. But when they state that you can reuse assets I feel like that doesn't mean you can reuse an entire game with minimal programmatic changes. Typically a game like this wouldn't fly in most jams, and it feels to me like this game wasn't made FOR THE JAM. I think people who make their game within the timeframe of the jam are more deserving of the prizes than a game that was made in a much larger time period than the jam allows with minimal changes added during the jam time.
EDIT: At the very least I would recommend adding a disclaimer to the top of the game's description that says it's a remaster of a game you've made prior to the jam. I believe it's misleading to not mention that this jam game had roots as another game before the jam.
The game is obviously fun, and has insanely good visuals which fits to the jam, but I kind of agree with Carson K. It looks and plays almost identical to your previous game. Seems like you repurposed a previous game to fit the jam rather than try to make something for the jam, perhaps because of the prize? Either way, its up to YoYo to decide for that, but for me personally, I don't think repurposing a previous game fits the jam spirit. If you tried changing the gameplay, and maybe added more things having to do with neon, maybe that would be different. I don't think taking attack items off was really that big of a change.