Master Combatibility G3 after editing

I’m making alterations to both masters across a weight range. This involves cutting and pasting the outline. After the alterations have been made I notice that the Master no longer interpolate. So I call up Show Master Compatibility and sort out the errors. All OK. However, G3 doesn’t always correct itself even though the outlines are compatible. The only way I’ve found to solve this is to Quit and Reopen then it’s OK.

It doesn’t always update right away. The workaround that always worked for me was moving the outline back and forth a unit.