Yura's Kai Ni was hyped for a long time (the very first hint probably being a cameo in the final chapter of Calm Seas published in February 2017) before finally arriving on June 23, 2017. See post #2748174 or post #2748477.
The time from Sara's remodel being hinted (December 2016 in KanColle Style 3) to being implemented (September 2017 post-event patch) was even longer though.
That so?It looks great on you, it really does!Thanks.Mhm!Yura Kai NiYou did it, Yura-chan!Let's continue working hard together!You know,Ah... yeah...You know?You know?That's right, I'm glad too...I'm really glad I finnnally got my Kai Ni.I've been thinking for sooooooo long, isn't it greaaaaaaaaaat that Kinu-chan and Abukuma-chan have theirs?Are you mad you had to wait...?It's not my fault, you know.I know.Slide...