Why is LVGL 8x and 9x running side by side?

As per the title, its a little confusing. Why is LVGL8X and 9X running side by side? What’s the rational behind this please.

I think it’s because V9 is a huge api change and have a lot o WIP on the roadmap but V8 is finished and there’s a lot of people still using so it is receiving bugfixes, V9 is receiving real updates.