Model AEG Competence B4100-1 though I expect there are several very similar.
I've removed the interior back wall cover over the fan oven element, because it's failed, but not noted which way round it goes ! :-(
From the faint markings on the back wall, I think the flat edge goes to the top and the largish, stepped cut-out goes at the bottom, with a smaller slot on either side. It would be good to have it confirmed though.
TIA