Originally Posted by
NickB
If the fare rules are coded to disallow it, I do not think it will work but nothing ventured, nothing gained, I suppose.
Of cause I understand that, but San Gottardo never confirmed the fares he was looking at. He just presumed it was due to the fare base as you explained. I have had more luck doing so on the KLM website therefor thats my advice.
Coincidentally I am on a trip at the moment with the outbound as in Business (J fare) and the inbound in Economy (E fare).