Agreed, when I have done a mass migration of old format urls I started with 302s to ensure that things worked then moved to 301s. I actually wrote a script that would capture and collect all urls that led to a 404 (just in case I missed an old format link).
301s also serve to inform search engines that your URL should be different and they update their index accordingly. My transition went very smoothly but it took prep work on my part to understand that 404s were inevitable and that I needed a plan to migrate that traffic.
301s also serve to inform search engines that your URL should be different and they update their index accordingly. My transition went very smoothly but it took prep work on my part to understand that 404s were inevitable and that I needed a plan to migrate that traffic.