I got an email from Facebook. It says; "Your App,, is currently accessing Graph API v2.3 which will reach the end of its 2-year lifetime on 10 July, 2017. We estimate 6 endpoints that calls will be impacted by this change and may stop working after the automatic upgrade push. To ensure a smooth transition, please migrate all calls to Graph API v2.4 or higher. Use the API Upgrade Tool to understand exactly how this change will impact your app.
Note: If you do not see any impacted calls in the API Upgrade Tool, your app/code may not be affected by this upgrade.
Visit our changelog to see the full list of changes in all Graph API versions."
I couldnt understand something clearly. How can i test my changes before upgrade? How can i test app with that changes? I should test cause' its big app so users shouldnt affect.