Was on a YYZ-BDA back in April, and I noticed a young white lady from Y freely visiting the J loo with no obstruction from the incharge who clearly saw her proceeding through the curtain.
10 mins later, a young black man tried the same and was turned back to the back of the plane.
Later in the flight the same white lady tried and was turned to the back.

Hate to play the race card, but that seemed a bit out of order.