Well those definately aren't canon. Found a whole page on a Korolev Class .........
http://asdb.homestead.com/Korolev.htmlAnd this ............
A U.S.S. Korolev NCC-2032 was listed in "ST VI: The Undiscovered Country", it is not known whether it is the class vessel of this class. If it is, and considering the nature of the ship names and the consequent duration of the class, some sort of Oberth variant would not seem unreasonable.
The LUG RPG supplement Ship Recognition Manual, Volume 1: The Ships of Starfleet calls this class a Surveyor (310m long, 12 decks, in service from 2352), gives a description that makes this class a member of the Ambassador 'family' and lists the U.S.S. Korolev NX-59387 and the U.S.S. Gathev NCC-61628. The earlier U.S.S. Korolev NCC-2032 is said to have been a Miranda.
I question that..NCC-2032 denotes an Excelsior Class