Some rumors has confirmed that UI 8.5 is releasing in this week and it will start rolling out from South Korea within this week and then other regions. Hopefully if they don't delay as usual.
That's true, they doesn't had a solid plan even i heard some news, saying that "The update was delayed due to some public holidays in South Korea and they couldn't launch this update last week. I never seen this in Apple in terms of software updates.
Users with S25 Ultra still haven't got this update yet and as always 24 Series will get update few weeks later. I also agree with that Apple always have their strong plan and commitment.