This site lists Safronova as a former Kirov principal. In the Mariinsky Theatre, I have seen books with her dancing with Soloviev and other Kirov stars, with her in principal roles. Just calling her a Maly soloist is equivalent to insulting her - just imagine saying that Kolpakova was a Maly soloist. Safronova taught Alina Somova and Elena Vostrotina from 2000 to 2003, 5th to 8th year, the graduation year. She was not a substitute for Kovaleva.
You make it seem like Safronova was not a highly regarded ballerina and not a highly regarded teacher, when to the contrary, she was highly regarded as a Kirov principal ballerina, having danced leading roles with Soloviev, and she was also an important teacher at Vaganova for many years. http://www.smithsoni...html?c=y&page=7
This link contains part of an interview with Safronova, in which it states she started at the Vaganova Academy in 1938. It also talks about the stringent weeding out process throughout a child's time at the Academy, during which only about half of these students who enter the academy actually graduate. Safronova would have graduated then in about 1946. http://www.ballet.co...tchelkanova.htm
This shows Ekaterina Chtchelkanova, a dancer who was part of Safronova's graduation class of 1988, so 2003 was not her only graduating year since she had a graduating class in 1988 and probably many other years. Incidentally, the one year Irma Nioradze studied at Vaganova, after graduating from Tbilisi, her teacher was Safronova.
Finally, 2003 was not her last graduation class as you write. She was also teacher of the 2009 graduation class which had in it 2 potential Mariinsky superstars, Yulia Stepanova and Nadezhda Batoeva, both recently promoted to coryphee, plus Mariinsky Tatiana Tilguzova and two Mikhailovsky highly used dancers, Krasyuk and Kiseleva.