Hmm I guess more backstory needs to be made before AGE 16 DOOM YEAR comes. I mean the characters we don't know too much about are
Julian
Lonely Marioness Girl
Duke Boy
Blonde Brother
We do know a good amount on
Hal
Blue Brother
Marioness Boy
Tsundere Tomboy Red Head
So I think once we sort of get a bigger understanding on all these characters + plus Lippe's own goals get achieved. Then we will get a substantial timeskip.
At least that's what I think....