In my defense it wasn't the earliest time of day when we had that conversation errol. I was looking at Dia sickle instead of luna sickle, and yes you need to IB>jump perfectly to punish that.
3C: 16F blockstun, 14 on IB.
Sickle: 17F startup plus the time it takes for it to reach you.
you have barely enough time to IB>superjump out.
Off of blocked 5D I will usually mode change, throw out a luna sickle anyways, or act parser Cavalier. you can technically punish cavalier on IB, but it pushes you far enough that it isn't an issue.