Friends made a reservation for an upgradeable B class fare on nwa.com for a flight from AMS to SFO on the M 11. Their seat reservations are 7 EFH.

They have received conflicting information regarding the seat assignments on the NWA PE line. 3 reps have said these are coach seat assignments.
One other rep said they paid for a coach fare and if this is a business class seat assignment, they will probably be moved to the back of the plane.

Looking at seat guru, it looks like it is WBC and there is no 7H--a closet is in that area. On the klm website, it appears to be WBC , but because the HJ seating is staggered, it is difficult to tell if H would be in Row 6 or 7.

Could someone familiar with the M 11, please clarify the seat plan?
Since the fare is upgradeable, it seems that if those seats were given to them, that they should be able to retain the seats if they are WBC.

Thanks for your assistance--we are totally confused. Obviously, they do not want to be sent to the back of the plane and prefer to have WBC seats--which, of course, is why they purchased an upgradeable fare.