For any of your files that have an expiration date you are able to attach this to the file upon upload.
Taskbox will then remind you in a specified time period before the document is due to expire, so you will always be prepared.
If you have documents that are subject to change or evolution, these can be version controlled within Taskbox.
Simply make an edit to your files, and taskbox will create it as a new version if you would like.
This means that you can always be working from the most up to date version of a file - and wont get caught out.