How can they sell the debt on if it's agreed to be written off after X years? That would breach the original loan agreement and make the debt worthless. Wouldn't it?
I mean it is happening already... https://www.theguardian.com/money/2017/feb/06/universities-minister-announces-sale-of-student-loan-book
In theory, all it should mean is that the loan is paid back on the same terms to a private company (Erudio), in reality, it means that the collecting is more aggressive and often results in mistakes like this https://www.theguardian.com/money/2016/apr/08/student-loans-firm-erudio-leaves-graduates-fuming-over-latest-error
I've already received a letter in error telling me that I had to start repaying and mine hasn't even been sold off yet...