Same happened with me. Here is the idea :

> Here’s the simplest solution I could come up with:

> 1. Serve the current site from a subdomain (e.g., 2017.ar.al)

> 2. Make my 404s into 302s that point to the previous version of the site.

> 3. If I change the site again in the future, rinse and repeat.

> I call the technique 404 to 302.