A few recent developments changed the map of coverage provided by the Russian early-warning radars. First, Russia began operations of a new Voronezh-DM radar in Lekhtusi. The radar has been operational for a while, but only recently Sean O'Connor, who maintains a very interesting site IMINT & Analysis, located it on the map. Thank you, Sean! The radar is at 60 16'31.47"N 30 32'41.96"E. A similar radar is under construction somewhere near Armavir, but that hasn't been identified yet.
The radar is Armavir is supposed to close the gap that has been created by the decision to stop using the radars in Ukraine - in Sevastopol and Mukachevo.
I should note that the size of the radar fans on the map do not necessarily reflect radar detection ranges - these are normally larger than shown here. Also, there is no information on the angle of the Lekhtusi radar fan - I assumed that it is close to that of Daryal radars.