@HenrykDodwel @Dreecko
From what I've been able to gather (from reading this and https://mangadex.org/title/46520/these-two-will-be-married-in-100-days), it seems like each chapter/day is only representative of real-life days rather than manga days (noticeable by how previously in this series, one chapter was school and the next was night of the same day, likewise for the linked series).
The only thing that I've seen that may debunk that is that in the other series, towards the start when it carried on from an event of the previous day, it would have a caption says "x days ago". Though that stopped later on.