What's the time delay for Blog posts to update RSS
 

I have the RSS feed of the blogs (all blogs, not individual ones) posting to my twitter account. However, there seems to be a huge delay in the RSS feed showing new posts. At the moment, there's been two new posts done that the RSS feed isn't showing up.

All the blog posts are visable to guests. The front page shows them instantly. But the RSS feed still doesn't show one that I made 4+ hours ago now.

I checked the Scheduled Tasks area, but couldn't see a setting anywhere there. Is there anywhere I can check? Does anyone know how often per day the RSS feed is updated?