Upgrading to 3.0.1 from 2.1.9

Yes, you need to schedule work time during which your app cannot be accessed, a workaround could be:

• duplicate the current database into a new one, you will use the new as a test for release
• apply all the SQL changes to the new database (you may need to follow up all the news to see where we required changes to database from 2.1.10 to 3.0.1), save the queries into a file so you can execute them later on the production database when it'll be the time
• install Combu 3 on a new folder so you can still support both versions until you're ready (then navigate to  http://yourserver/your_combu3/_setup  on your browser to get/create the configuration file content, remember to set the new database for the connection and not the one you're using in the current live version)
• duplicate your current Unity project into new one, delete the folder "Combu" (move out your own files from there eventually) and import Combu 3 (the URL will be the new Combu3 folder that you installed above)
• do your changes to support Combu 3 (create new app on web admin, copy AppId and Secret Key in Unity, etc)
• when your new release is ready then you can execute the update queries on your production database (make a backup copy first), but you need to deny the login to old users because the new system is not compatible with the old one (we have the App entity now in Combu) for example by returning false in the login actions (I can help you in this when you'll be ready to release)

Thanks for the reply. I'll let you know when I'm ready to release