The official timeline has always been the Ally storyline, even after the Soviets meddled with the timeline and introduced the Empire of the Rising Sun into the conflict. So in a way, Einstein has only been erased once. But then again, given the existence of multiple time machines and multiple different reasons for using time travel, Einstein may have been killed infinite times across the multitudes of creation.

The Great World War 2 was the Soviet invasion of Europe. World War 3 started when the Soviets launched a surprise invasion of America. Following the Soviet timeline intervention, the Third World War began much like the first, with a Soviet steamroll over Europe.

So in the official timeline, World War 1 happened as it did in the history books. World War 2 was the failed Soviet invasion of Europe. World War 3 either began with a surprise invasion of America or a lightning attack in Europe with another surprise attack from the Empire of the Rising Sun. No matter how you look at it, there have only been two major wars between the Allies and Soviets.

Yuri's time travel was like a small pocket universe. He co-opted the original WW3 to his purposes, but intervention from an Allied commander reset things to MOSTLY the original WW3, only to be immediately overridden by the Soviet time travel, possibly moments after fixing things.