I think between 1200-1300 chapters which would take roughly 5 years seems right. Feels like it will end sooner rather later so can’t see it going on for longer than that unless he cuts down on the number of chapters
The issue is we have to think about "real estate" in the plot and theres just so mucj we dont know yet.
- We dont know exactly when Egghead will end. Id say a good guess is probably between 1130-1140 at the rate it is going.
- We cant confirm if Elbaf is directly next, but lets assume. Even if its short (50-60 chapters), that still puts us at roughy 1200 lol.
- Then if we are confirmed to be going to Elbaf, then we also should be going to Law's original destination. If thats not Lodestar, its another thing on its own, but my guess is its 4th RP related anyway. If its the the big fight over it with the 4 Yonko involved, it can easily last 100 chapters. Wano's fights alone almost lasted that much lol
- If not there, then Lodestar/Laugh Tale
- It also doesnt include the "possibility" that the WG war is separate. If not, then thats just a larger war at the end of Grand Line.
This is without me really going into plotlines, but rather what we "should" expect in terms of the journey
Tldr: 4 Islands minimum after Egghead, not including Mariejois if we go.