The further north you go in the Trapps the earlier it goes into the shadows (the cliff bends a little). The yellow wall being further north means sometime shortly after noon (1-2PM), compared to the Uberfall (south) which isn't until like 3PM(?).
Google Earth is a useful tool for this sort of question. You can plug in a particular date in the past and see a satellite photo of the sun exposure on the rock.
Although I couldn't figure out the google earth trick, it did get me to look at the map and that bend isn't as pronounced as I remember it being, though I know from experience climbing near the yellow wall that it does go in the shade sooner. There's obviously a few additional things factoring into when parts of the cliff go into the shade sooner/later than others.
The further north you go in the Trapps the earlier it goes into the shadows (the cliff bends a little). The yellow wall being further north means sometime shortly after noon (1-2PM), compared to the Uberfall (south) which isn't until like 3PM(?).