I did some bleach discharge thing years and YEARS ago - worked well for creating a new fabric that 'matched the one I had started with. You had to neutralise the bleach with something with a logn name - I want to say Sodiummetabysulphate - but don't know where that came from!
ANYWAY
As I can't give precise instructions - google it. I know if you do it right it won't weakent the fabric toooooo much!
I also think the swaping with board members idea is a good one!