Don’t know if this will help you or not, but you could dry clearing the cache before trying to get the values. Do acf_delete_cache();
The acf cache is just an extension of the wp cache.
I’ve never had a problem getting new values after they were updated, so I can only think that it is definitely something in once of the caching systems that you’re using. From what I know of W3TC it replaces the WP DB cache with it’s own system. I’ve never used W3TC.
