For a short period I was Level 6, during which time I completed 50 edits and accrued $20 of payment. I am not to be paid this money, however, because it has not reached the $50 threshold for payment. I can't hit that threshold because I am no longer at Level 6, and am unlikely to return to that level.
My work on those 50 edits was just as valid as any other work. It seems unreasonable that the money earned from them should be withheld because I am no longer able to complete edits.
This could be resolved by paying editors any money outstanding when they cease to be Level 6 (and therefore cease to be able to carry on editing.)