This paper is pretty unbelievable to me in the literal sense. From a quick glance:

First of all they couldn't even bother to check for simple spelling mistakes. Second, all they're doing is asking whether a number is prime or not and then extrapolating the results to be representative of solving math problems.

But most importantly I don't believe for a second that the same model with a few adjustments over a 3 month period would completely flip performance on any representative task. I suspect there's something seriously wrong with how they collect/evaluate the answers.

And finally, according to their own results, GPT3.5 did significantly better at the second evaluation. So this title is a blatant misrepresentation.

Also the study isn't peer-reviewed.