So, in the timeline before Gaku arrival, Hibino just accepted the defeat without fight after the pre-matured attacked by Kougetsu that was led by Noboru with just the Sophomore and Hibino was willigly agreed to be allied and befriend with Harumi again because Kanamori & Wagatsuma were no longer around.
This time, it's literally different scenario. The butterfly effect of Wagatsuma & Kanamori staying in Kumine and the war between Kougetsu & Aoba with Yuzuki had been released from Juvenile Detention, really make a huge change and an impact of a story than before