Thank you. The settings now stick as per the update.
However, there is a problem when AMP is activated. My home page images disappear and the formatting of text has been changed to a font that i don’t use.
Also the title of the page appears and the header menu is gone.
Seems that the AMP plugin messes with all of the css.
You can disable all Gillion theme AMP optimization in the theme settings as shown in the attached screenshot but yes the AMP changes the appearance of the mobile website to accelerate website loading.