That's what confused me, because it's day 366 (v0.7.16) and I still haven't gotten it. Not even the initial scene where Rae suggest doing the celebration.
I forgot to follow up here, my apologies. Have you grabbed the swimsuits for Blair and Yona? It won't trigger the event without them. (Once you talk to them by the pool, they'll discuss their swimsuits, come back in a few days, in the afternoon and it should progress).