I currently have my permalinks set up as day and name. Have posts going back to August 2010 with that structure. Now that 3.3 removes any performance penalties with use of categories in the permalink, is there a reliable method for changing without 404 errors or need for extensive 301 work?
I have seen a number of plugins for this but most have fallen out of support or have a number of users reporting loopback errors. Would adding info in the htaccess be enough to fix this? Any possibility that WP will allow setup so that permalinks could be setup as 'past' and 'future' structure?