There have been some developer questions submitted to support regarding what subscription key to add to unlock the 30 day limit. The 30 day limit is to allow partners to build sample applications. You should enter the customer ENTERPRISE subscription license key for a production application to unlock the application. It is the same key you would use for the Sugar Instance.
If a partner is using their own subscription license, the subscription will be validated but you will still be limited to 30 days since it is not an customer enterprise license. You can make an enhancement request if you need a longer limit than 30 days but that amount of time seemed adequate for most temporary demos.