Is it still 404 for you if you don't mind me asking? From what location?
Over the weekend AWS reported my instance health went to Bad for a bit not sure why.
Western Canada, but I don't think that's the problem. I'm on my phone, and just noticed it looks like it loads, then redirects to /mobile which is where the 404 actually appears. Switch my phone's browser to Desktop mode send to load fine, although a little awkward to use :)