correction: Rostov-on-Don is the larger city, with 1.1 million inhabitants

To me it seems that an extra zone is needed, which starts with LMT util 1919, later follows Moscow since 1930, but deviates from it between 1 October 1981 until 1 April 1982.

I suggest to call this zone Europe/Yaroslavl, because Yaroslavl with a population of 608'000 seems to be largest city in the deviating area.