Much cursing and banging by SWMBO dragged me across the kitchen so see her trying to force the grill pan into the top of the oven - " won't go in, damn thing !!"
The logic of "it went in before, and because it is not going in now means something is wrong" does not compute in the female brain in my opinion ( and experience).
The reason for it not going in was that the grill heating element in the top of the oven had become detached and dropped down - easy to see.
What is curious is that the oven heat cycling plus I suppose aa bit of vibration from the fan had loosened off the 2 supporting screws to the point they had dropped out. But where had they gone - they have never been seen and no one has had roasted screw/washer in their sunday joint or sticky toffee pudding. Odd !!
Repaired from the odd screws jar from the workshop.
Rob