Hidden in Paradise: THE DAY BEFORE SUMMER (prequel)

THE DAY BEFORE SUMMER: what happened before the first season in paradise?
Prequel

Just before leaving for Camp Paradiso: a day of making new plans for the summer, but also for the distant future. Also a day of surprises. So how did it all start? Why did things go wrong in relationships? How did the summer crush start? And why did everything get so complicated at the beginning of the summer?

"There's also progress in relationships: you used to look around a little and get married right away, but now they just take a little time to figure out who they're most on the same wavelength with, right?"
– Measure.