Updating from 3.8.1
 

I'm quite clueless when it comes to vB maintenance so please bear with me. I haven't updated anything on my board in the past year and I see that 3.8.4 is the latest stable version. I just went to the members area to download the update and when I click through the only available download is 3.8.1. Where can I get the latest version?
Thanks,
Dave