Originally Posted by
BubbaX
When you buy the ticket, and go to the website/app to check your booking, you will see an invitation to upgrade with miles. If you click on that, it will always lead to a page that says "give FB a phone call". When you call them, they will tell you an upgrade is not possible.
This was discussed recently, you must use the same national variant of the website that you used to buy the ticket. i.e. if you bought your ticket on klm.be you have to check the upgrade on klm.be, klm.nl nor airfrance won't work.