Thanks for doing that research. By design the tz database has separate entries only for regions that are in different countries now, or where clocks have diverged since 1970. This is to economize on our maintenance effort. Otherwise, we would need hundreds of zones just for Indiana, and thousands worldwide; our lives are too short to maintain all that stuff. Because of this rule, the 1945 divergence doesn't justify having two separate entries for Berlin. However, we should have the correct entry for Berlin, which raises the question: where is the commonly accepted center of Berlin? If the center is in the former Soviet zone, tz's Europe/Berlin should use what is in the proposed Europe/BerlinEast zone. If Berlin's center is in the former west-Berlin zone, Europe/Berlin should change to match what is in the proposed Europe/Berlin zone.