I changed my site about 4-5 months ago to send 404 response errors when my dynamic content can not longer be displayed on my site.
Now, Google webmaster tools keeps sending me messages that they are finding an increase in not found errors and that I should check for broken links, etc. However, when my content expires, it removes all links to the expired content right away. Is there something else I should be doing, or be doing different to let serps know my content is going? Or should I not give a 404 response and just redirect to relevant content?
When looking at some competing sites, I see that their content cannot even be found in Google search after their content is removed from their sites...but me giving a 404 seems to keep the indexes for quite some time.