Late model MiG-21 with VVS

By 1980s the mig-21 was being largely replaced by mig-23/29
however the Nbis and bis versions were still very capable aircraft esp. since the floggers/foxbats were not the best to tackle very agile opponents

did the VVS have these aircraft in service in 1980s ? in the OOB of 1989 in airforces journal i saw of total of only 370
were the many more kept in reserve ?