Webtop Shrink and Expand icons not updating when changed in General Branding Settings

I have changed from the default expand and shrink images to a set I built to look more in line with the branding of our Institution. The issue is, after applying the policy, they have not updated.

To change the icons i did the following: Access Policy > Customization > General > Branding > Webtops > "webtop name" > Full Webtop Settings. I then changed the Expand Section Icon and the Shrink Section Icon however no change on the actual webtop.

Am i missing an assignment somewhere?

Thanks in advance