I've been away since Dec. 23 and I am trying to find out if there's a way to see all the threads/posts that I've missed since then.

I've been away since Dec. 23 and I am trying to find out if there's a way to see all the threads/posts that I've missed since then.
At the top of the page click on "view new posts" and it will show you all the threads that have had new posts since your last visit.

I tried that but it only goes back a day or two. I'm trying to see the threads from Dec. 23.

After I was MIA from the boards for a few weeks in September I had to scroll through all the forums and look at the dates of the last posts.