I had booked a roundtrip flight on China Eastern a few months ago for travel between SHA-TSA in early December. Now it turns out I won't need the return portion back to Shanghai. What are china eastern policies for getting a refund on the return portion of the flight?

Travel agent says I need to pay 1000RMB to cancel the entire thing and rebook a one way. This essentially says don't bother canceling since the flights are more expensive now, but I want to check with others before accepting my agent's word.