What PhoneArt is saying is that instead of releasing major changes with the new One UI update debuting with the Galaxy Z Fold/Flip, Samsung will hold off releasing them and reserve these changes for the One UI X.5 iteration, which will debut with the release of the flagship Galaxy S series.

Leaker PhoneArt reveals Samsung’s new One UI update system. | Image credit-X
The leaker makes a point of stating that Samsung will continue to consider the Galaxy S line the flagship priority. This is why Samsung won’t introduce all of the new content it has for its latest One UI release until One UI X.5 is released with the Galaxy S series. To reiterate, typically, you’d expect One UI 8, debuting with the Galaxy Z Fold 7, Galaxy Z Flip 7, and Galaxy Z Flip 7 FE to have all of the new cool features and content.
In other words, Samsung will delay the release of some new features that you’d normally expect to see with the debut of the next build of One UI until the One UI X.5 release that will be included with the release of Samsung’s next Galaxy S series flagship line.
This will be confusing to some Samsung Galaxy fans. What we can tell you is to expect the Galaxy Z Fold 8 and Galaxy Z Flip 8 to be released next year with One UI 9. This means that Android 17 will debut on the Fold 8/Flip 8 next year.