I don't know but it doesn't really matter. Luffy WILL defeat an admiral and a second clash with big mom has been foreshadowed more times than I can count.
So there is absolutely no reason for Luffy or any of the straw hats to surpass their yonko crew executives this arc. The shear fact that Luffy is teaming up with his rivals to take out Kaido should indicate that much.
The thing is if it’s too much of a power jump now, it will be too much of a power jump later as well. I mean if Zoro doesn’t get to YC1 level now because he needs multiple arcs and power ups, I don’t see how and when he’ll be ready to beat the likes of Fujitora, EoS Shiryu and Mihawk. Wano is not the end of One Piece but the manga is really close to its end so they don’t have much time left to get to the level they need to be at in the end.
We don’t know whether Luffy will team up with anyone to beat Kaido but he will beat him regardless and reach Yonko level by the end of the fight. Zoro and Sanji need to beat King and Queen, with or without help.
Everything points towards Wano arc being THE big post timeskip arc before the end, the one in which the SHs will reach a major milestone. The whole post skip story has led up to this very moment and this is the arc in which Luffy is supposed to prove he’s worthy of the Yonko title (whether he actually becomes one doesn’t matter). So them surpassing the Yonko crew in a later and less important arc would be anticlimactic and inappropriate in my opinion.
Besides, there’s absolutely no guarantee nor indication of Big Mom being the main villain of a future arc. And 2 of her SCs have been defeated already so who will fight Zoro, Sanji and Jinbe ? Smoothie and Snack ? Meh.