[aorist]

This specific analysis isn’t p-hacking because although they conduct multiple tests, they report all of them rather than just the statistically significant ones.

They should however account for multiple testing. The Bonferroni correction (which is conservative) would set the alpha level to 0.05/5=0.01, for which the 1 day after result is still (just) statistically significant.

Not to say there couldn’t be other problems.