To me it could go either way.
- Flashback ends here: 1102 starts in present time, Zoro defeats Lucci, we see Saturn about to kill Bonney, we see Kizaru get back up, in the final page we see Luffy get back up on the ancient robot
- Flashback doesn't end here: 1102 covers the remaining life of Kuma
It makes no sense to drag this in 1102 as there is barely anything important left. The only thing that would matter here is the ancient robot and Kuma connection but this can be shown later.
Narratively speaking, the flashback ending here is much much more fitting than it getting dragged on.
- Flashback ends here: 1102 starts in present time, Zoro defeats Lucci, we see Saturn about to kill Bonney, we see Kizaru get back up, in the final page we see Luffy get back up on the ancient robot
- Flashback doesn't end here: 1102 covers the remaining life of Kuma
It makes no sense to drag this in 1102 as there is barely anything important left. The only thing that would matter here is the ancient robot and Kuma connection but this can be shown later.
Narratively speaking, the flashback ending here is much much more fitting than it getting dragged on.