I purchased Avios on ebay which have been rejected by British Airways. They were transferred to my BA account after paying for them almost immediately, but BA say they are stolen and threatened to close my account and cancel future flights if they were not purchased through the proper channels. Ebay were contacted but did not seem that interested.
Just beware of Avios being sold in any quantity. I not only lost the money by purchasing the Avios from ebay sellers but had to by additional legitimate Avios from the BA official site to cover my flights.
There are still sellers today advertising so be careful.
