Hi EE. All of our Events on https://abamedicine.com/ started 404ing. I turned off plugins with the same result. The only thing that is different is I did install Woocommerce and Woocommere Memberships recently but I have deactivated those and am still getting same errors.
Events going to 404 can happen if something flushed permalinks at an unexpected time when EE’s rewrite rules haven’t been added yet, as a one-off its not a cause for concern but if it continues to happen please let us know so we can investigate further.
To fix this on your site go to Dashboard -> Settings -> Permalinks.
You don’t need to do anything on the page as opening it flushes permalinks but if thats feels wrong, just hit save without making any changes 🙂