The recurring tasks feature is currently a beta feature that is available to all accounts. Previously it was only available to our early adopter customers, but it has been released as a beta feature for all accounts. We are in the process of collecting feedback and iterating on this feature to get it ready for its full official release.
Please be advised, however, we do not have a sandbox option available. Any changes made to your tasks will remain in place after the official launch.
If you have any questions about recurring tasks or how the beta feature works, please contact us and let us know.