All four raven chicks appear to be doing well. They've grown quite a bit in the 12 days between these visits. The chicks are now ~3.5 weeks old.
I'm guessing they probably have a couple more weeks in the nest. After fledging, they'll stay in the area for at least a few weeks, still being fed by the parents.
It's fun to see their glossy feathers, and the development of classic raven postures and behaviors.