Sent mine in at the time - they cleaned the sensor, but it has oil spots again now. I have also cleaned the sensor myself several times. I love many things about this body but this bit is frustrating. I guess I will send it in again for cleaning if I can't resolve it myself.
1Dx, 5DMKIII, 600 II, 300 II, 200 f2, 135 f2, 85 1.2 II, 100 2.8 IS, 24TS II, 70-200 II, 24-70 II, 16-35 II, 100-400 II