Sometime to keep our comunity "clean" we write a post and instead of replaying to it with updates we simply modify it.
User read that post only when it's new and never come back to read it since there is a new reply, so they will never be aware that the post has been updated.
My suggestion is to make an option douring editing the post to flag "Mark as updated", then the post will appear in the recent post list with an "Updated" icon. After user read it it back to normality.
This will contribute in keep comunity clean and user to read updated posts.
