Originally Posted by B747SP

Ran into the same situation in 2013. Needed to cancel a return leg from a RT US-EU award ticket, and was told that the flight could be cancelled but there would be no miles refund. Ended up making changes to the award reservation online and changed the return leg to an intra-EU destination, which resulted in the difference of miles being refunded. The now much cheaper return leg had to be discarded without a refund though.