I'm working on a Magento 2.2.9 website that somebody has already built before me. I'm trying to change the layout for the Home page and I'm really confused about which file I should be editing. I've found that the layout will be either in default.xml or in cms_index_index.xml.
I also went to Admin->Content->Pages->Homepage, and "CMS Home Page" shows "Ultimo Home Page 1", "Default Web URL" shows "cms". The problem is that I have 8 Ultimo Home pages and I also have 8 demo.xml files (demo1.xml, demo2.xml, demo3.xml, etc.), and when I search for "Ultimo Home Page 1" it finds it in every demoN.xml file so 8 instances. And I'm not sure which one is being used for the Home page. I'm assuming it's demo1.xml, but I have no proof for that.
So, how do I find where the layout for the Home page is being configured?