Rofl it might take even longer. A big issue this arc has is it entirely endloaded its villain presence.
The first ~50-60 chapters of Wano didn't really have anything to do with any of the F6 (outside of Page 1) and only Jack/Queen got small bits of characterization in portions of the arc. If you go back to something like DR, a lot of Doflamingo's crew members were central to a lot of the early and mid game content. Even Kaido has been endloaded in the arc, with barely being featured until the raid.
I'm honestly afraid (well, partially excited cause its fighting) this arc may go on for signficantly longer than expected. Not only so we have to finish setting up fights, we have to get to the point where Oda starts dropping the villains, which may take longer than we think cause of the points above (he has to characterize them). Then after this, he has to do each fight, probably 1-2 chapters. That alone will take anywhere from 8-20 chapters depending on how long he decides to spend on each villain.
I'm just personally not confident anyone will fall for at least another 10 chapters, and thats highly dependendent on what he decides to dedicate chapters to. We still need to dedicate panel space to get Sanji from where he is now to a calamity, likely the same with Yamato.
Its going to be fun....