Generally, FileCloud releases happen every 3 months coinciding with the end of quarters Q1, Q2, Q3 and Q4.
If there is a critical bug or issue identified, then an intermediate patch release is also done as soon as possible. Releases are announced on our blogs as well as in our email lists. Your FileCloud Admin control panel should also notify you of any updates that are available. You can also look at the release notes to determine the changes that have happened in any specific version.