Thanks for responding,
@Matt: I'll try Mitchell and up the min samples first, then up the AA if that doesn't work. Rendering now.
@Oshyan: Yes, they are imported jpg textures for all of the objects. Is there a TG problem regarding jpg textures or their sizes? The background is something Ulco did for me, I haven't tackled yet why the mountain shadow is changing shades, not sure about that yet. I did set the strength on surfaces to 2.25 to brighten them up some (problem?). Defer atmo/cloud is enabled, atmo samples = 10
@Hannes: I rendered a cache every 5 frames (because there's lots of foreground grasses) and interpolated every 5 as well. Detail blending is already set to 1, and RD region padding is .5