That’s best case scenario, yes. And if they wait for D&D’s trilogy to be over (2022, 2024, 2026), and then then do Johnson’s trilogy (let’s say 2028, 2030, 2032), that would mean Episode X comes out in 2034 at the earliest, 19 years after Episode VII kicked off the ST, which itself was 16 years after Episode I began the PT.

That’s assuming they stick to an every-other-year cycle, don’t overlap trilogies, and don’t do standalone movies. If they do one per year and overlap trilogies, Episode X could be as soon as 2028, which is 13 years after VII.

My best guess would be to expect Episode X to come out sometime between 2030 and 2035, and we’ll have until at least 2027 (the 50th anniversary year) for them to pretend IX is really the end before they announce the next numbered trilogy.