Again I promise you that it is very unlikely that only copper is a problem. Copper becomes biounavaible because of so called superoxidizer which are mercury and lead. Until these things are not out of the body you will go in cricles. In natural ways the body can handle copper very good, even high amounts of it. It is only when lead an mercury are interferring with this process that copper becomes a problem.
I wouldn't rely too much on hair and challenge tests. See cutler on this.
And for lead: The disappearence of it on the hair test is no signal that it is completly out of the body. The bones store so much of it so I would be careful when more is released from storage site.