We are really sorry to inform you that this feature/options is currently not available in our theme but as you have suggest us, we will think about it and we will soon add this feature/options in our upcoming updates. But for now you can do it by customizing the theme file with the help of child theme or if you have problem in doing coding then you may wait for the update or you may contact near by developer for it. We hope you understand.
Yes you can include in header.php with help of child theme but it may affect in responsive design of header part but we can provide you one suggestion for this that you can show the banner in desktop version and complete hide in responsive design.
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