Usually the connection will just time-out or reset. But a couple of times while trying to reload a specific vendor or item page after it's timed out, I will get a 'File Not Found' error. This is for URL's not pointing to a specific file (like a product listing).
I'm only posting this because I wasn't sure if this could be extrapolated to give us an idea if all the downtime lately has been from DDoS's, server migration, or code alteration. But I admit my knowledge in this area isn't the best, so I figured I'd ask the sub.
That's normal and has been happening for a long time now, keep retrying to connect.