Complex sentence: The total blockade was lifted on 17 January 1919 when the Allies allowed the importation of food under their supervision; however, food deliveries were delayed until 8 March 1919 when the German government agreed to the restrictions imposed by the Allies.
Split into simpler sentences: The total blockade was lifted on 17 January 1919 when the Allies allowed the importation of food under their supervision. Food deliveries were delayed until March 1919 when the German government agreed to the restrictions imposed by the Allies.