HI SeattleK
My husband is a fast oxidizer too and he has been taking quite a bit of copper. His retest does show a copper dump, though. The reason for this, as I understand it, is because the copper you taking actually has a binding protein in it, so it will bind to the toxic copper your body is hoarding and then flush it out.
He was taking a certain kind of copper and it made him so sick he would throw up. Changed brands, though and now he tolerates it fine.