XP after last-minute upgrade?

Hi, I still need a few miles and am about to book an economy class ticket with KLM. Assuming there will be a spot on one of the two flights in business class (out- and inbound), and I can buy a spot last minute, will I also get trip XP for that? I namely need a few more to qualify for a higher elite level.

 

You will only get XP for the original booking class, unfortunately.

 

Thanks. That's good to know. I don't want a bad surprise afterwards