I don't quite understand the part in this about Google Maps changing the route. When I put in directions to Google Maps for Yakutsk to Magadan it still goes along the P-504 (aka Kolyma Highway or "Road of Bones" [0]).
The Wikipedia page also says that the road is called the Kolyma Route "since it is the only road in the area and therefore needs no special name to distinguish it from other roads"
[0] https://en.wikipedia.org/wiki/R504_Kolyma_Highway
Edit: Okay, it was pointed out in the comments below that Google maps does go on the correct route now. It is the same general road, but there was a section called the "Old Summer Road" that had fallen in to disrepair but was shorter.