Graph Editor Points Lost In Rig Detachment?

[RenAi]

So let's say I'm using a rig on a model and that faceposing only works when no rigs are attached. So I detach the rig, do the faceposing then reattach the rig. Then I find that all of the black points in the graph editor are no longer there though the lines are still as they were before, so while I don't lose any animation work, I can no longer change anything I've already posed/animated.

Does anyone know why this happens and how I can fix this issue?