Everything learned this year is relevant for next year as the rules are stable so developing will still be useful. Horner said that…
Didn’t they originally change concept in Barca 2022?
They will lose a lot of wind tunnel time in July due to being so high in the WCC
Of course it's useful, but that doesn't mean they will bring those developments to the track. RBR are severely limited compared to other teams with wind tunnel and CFD runs. Don't look at the percentages, that's fairly meaningless against the real world number of on wind runs they have against others.
They focused development of the RB18 on the suspension and floor for the RB19, combined with the lighter chassis we never saw last year.
The upper body was almost unchanged. There are lots of small details they don't have yet. I am certain that the RB20 will be another evolution of this car, keeping the floor and suspension the same as whatever is on at season end, and developing the upper body.
It wouldn't be a surprise to see the RB20 with different sidepods, engine cover, mirrors and other small vanes and winglets. These will be kept for next year, as there is no point running them now.
It could mean they lose some advantage towards the tail end of the season, but might set the bar again next year with new bodywork nobody has seen.