Those of us that had flickering in the earlier build only experienced it at 24hz - i.e. 24p media and Sync Refresh to Playback enabled. At least some (including me) got banding as well, again only at 24hz.
In the new build the flickering is resolved but the banding is present at all refresh rates (or at least 24 and 60).
Out of interest do you have Sync Refresh to Playback enabled? If not, that might explain why the banding is new to you.
Martorias posted a test clip that demonstrates the issue perfectly: HDR Slight flickering (Workaround available) - #211 by Martorias
Sam says he’s on the case, so watch this space (or the osmc github commits 
)