Hi folks, tried searching for this one but with no joy. Is this still possible? I know it used to be but have no idea if it still is, and can't find any reference to it online or on FT.

If so, who should I contact - KLM or CO? The flights I am looking at are intra-European so not a great business class product, but I have a stack of CO miles to burn off. I am CO Plat.