On v3.1.3 b11127 (and 3.1.3-b11894). Colorist is attempting to switch back and forth via hot key (and right-click / play) from a still to a clip currently being graded. The SDI LUT values are not being represented on the SDI output when viewing the still, but is visible on the clip being worked on.
This works on v3.0.3 however we need to grade XOCN, and XOCN does not work in 3.0.3.
Let us know!