There is a difference between the general oppression of the population and the persecution of the Church. The Church did have a period of respite from persecution from 1945 to 1953. (Stalin bestowed honours on hierarchs who had raised morale during WWII. He also received Metropolitan Elias of Lebanon with great courtesy and presented him with an icon of the Kazan Mother of God which Stalin had ordered to be carried into battle in a number of engagements, including Stalingrad and Leningrad.) The scale of oppression of the population as a whole continued after 1945 but this decreased after 1953 and the camps were closed in the late 1960s. The persecution of the Church by Khrushchev as great as it had been before WWII. Whatever I mention about Stalin must not be read as any sort of sympathy for him - he was a cynical, murderous tyrant.