The Kurds already had control of the North East of the country years ago, hence the first outbreak of war a few years back. The Kurds are problematic for the Syrians, Turks and Iraqis who all persecuted them because, none want to see an independent Kurdish state, because of

1. the resource wealth there
2. the Kurds were sabotaging the attempted building of oil and gas pipelines from Saudia Arabia to Turkey, on to Europe.
   However the Kurds are not a unified people, they don't even all speak the same language, hence no nation state has ever emerged.

I have now seen several reports that indicate the Syrian armed forces may have been told to stand down by Russia, to trap Western forces (including Israel) in messy conflict of attrition similar to that of Afghanistan.

In short, the conflict is not over yet.