You can switch between Stable and Experimental versions on your 7DTD server whenever you want via the control panel.
First, login to the control panel at http://cp.chicagoservers.co
Navigate to your server within the control panel. Once there, click on Switcher and then click the version of your game that you want to switch to:
This will delete all of your server files and then install the specified version that you selected. The server will be marked as Processing and you will receive an email once the process is complete.
You can launch this process whenever you want and as often as you want.