You may freely retrieve your game progress if it has been linked to Google or Facebook whenever you want to!

In order to download your game account, just simply do the following:
1. If you linked your game account to Google, add the linked Google account in the system settings. If you linked the game account to Facebook, you can proceed right to the next step.
2. Start the game, sign into the corresponding Google/Facebook account in the game settings (Settings - Account management) and download your game progress.