Mastery points: Individual score (grade score) not adding to champion mastery

A friend and I have been working towards rank 5 in the new champion mastery system and we've noticed that the number of points awarded for grade/individual performance weren't contributing to our overall mastery points. We checked by recording our total mastery points before the match (eg. 9825/12600) and comparing it to the total after the game. What we found was that the new total only added the points from the team contribution (the larger number you see in the postgame lobby), while the smaller grade number you see while hovering your mouse over the mastery icon wasn't being added at all.

Has anyone else been experiencing this issue?

Edit: for a specific example, I just played a solo match as Ahri. Champion points before: 2061/6000 Team points: 158 Grade points: 30 New total champion points: 2219/6000 Champion points difference: 2219-2061=158 So the +30 doesn't seem to have gone anywhere.