Removing drawers on Swift motorhome

I noticed another post in the caravans section headed "Swift Soft Close Drawers".

This reminded me that I have a problem with these drawers on my 724FB motorhome and I wondered if anyone might be able to help.

I stuffed one of these drawers with socks and I am sure that at least one pair, if not more, have fallen over the back of the drawer into the void below. I can find no access to the "space" below these drawers. I am not sure what is below the drawers - maybe it is just space for the rear wheel arch. 

The only way I can see to access the space below the drawer is to remove the drawer, but I cannot for the life of me figure out how to do this. When you pull it out it hits a stop of some kind. I think, typically, with drawers on runners, you can lift them up away from the runners; but this does not seem possible with these drawers. I am sure there must be a trick to this, but I am damned if I can find it. I bet it is obvious if you know it!         

Has anyone got any idea? I attach a photo but I don't think this will help much. 

Thank you in anticipation

Graham