Hi Tamsin
Thanks for the help but. To experiment I have set up two viewports side by side, one a Viewport of the model in elevation with display planar objects enabled. The other a Section Viewport with display objects beyond viewport enabled. On the model I have created a hatched surface object. In the Viewport (elevation) this displays as intended but in the Section Viewport it will not display. In both viewports class visibilities and overides are set identically and the depth range of the section is set to infinite
I have tried your suggestion of making adjustments in the advanced properties palette eg use original fill for objects beyond the section plane to no avail.
Looks like yet another thread for the wish list.