Can we have a timer (setting) for offline files to revert back to online-only?

We use Dropbox as our server solution. However, we often run into the issue of our hard drives constantly filling up due to too many files being set to Offline due to the large volume of work we do.

Rather than having to go through and set each file to be Online-Only' Dropbox had a timer system you could set (say 3 months) where Dropbox would then convert all the legacy 'Offline' files back to 'Online-Only'