Hyperinflation ended in 1924 following Grabski's reforms.
Yes, but did Grabski put a stop to the trade tariff war with Germany, whose Chancellor still refused to accept the new national borders with Poland, or the Versailles Treaty, which forced his government to acknowledge Germany's war guilt? If so, Grabski would have gotten Poland out of its financial straits and its war devastation, as Poland relied heavily on natural resource exports to Germany, Britain, and France in those days in order to regain the capital lost after 125 years of occupation and World War I. Remember, when the Central Powers occupied Poland, the occupation authorities depleted the resources necessary to rebuild post-war Poland, so Piłsudski had to rely on foreign loans, and military expertise, to build up Poland's presence in interwar Europe and in the Baltic. I don't think Grabski was sophisticated enough to rebuild trade relations with Germany, although I could be wrong.