Bleed in PDF export not appearing

I suspect I am being very stupid here, but I am unable to get PDF export bleed.

Per the enclosed screenshot, I have generated a page area equal to the crop area of the advert concerned, and on screen the bleed area extends onto the pasteboard. When I export it as a PDF - PDF1.3 which is what is needed - then as you can see from Acrobat hanging around behind Xtreme Designer Pro, the blue graphic does not extend onto the pasteboard, but rather gets cut off exactly where the crop marks are. IE the crop marks are in the right place, but the page outside the crop area isn't printing.

What am I doing wrong?

This would appear to be user error. The answer is to set a bleed margin when you do a custom page set up. Left here in case anyone else comes across it.

Glad you old the user what to do.