According to producer "Almaz-Antey":
Rif-M:
8 simultaneously engaged targets, 16 missiles per salvo. Distance (min-max) 2km-150km, Altitude (min-max) 7m-30000m. 48N6, 48N6D and 9M96 missiles.
Rif: 6 simultaneously engaged targets, 12 missiles per salvo. Distance (min-max) 8km-120km, Altitude (min-max) 10m-25000m. 48N6 missile.
Export version on 051C corresponds to Russian Rif.
That's cause they use two S-300fm systems which were bought in 2002 when HHQ9 was immature.