the single post layout cannot be set with right+left sidebar.
into the menu “blog config” this option is not available and even if in the single post I “ovewrite the default post layout” I cannot get to have two sidebars…
The “Overwrite the default post layout” is valid for pages (post type) only. The blog single post (custom post type) are set up from General Options > Blog Options > Single Post Layout. And this layout (left+right sidebar) is not available for it.
