Sadly the fourth ship of the five units in the BELORUSSIJA-class has now disappeared and scrapped, the former KAZACHSTAN (built 1976). If I remember correctly, the DELPHIN is the first, the BELORUSSIJA herself.
Correct, the DELPHIN is the ex-BELORUSSIYA indeed. She is also by far the best maintained one, as she had a major refit in 1993 (after a drydock mishap in Singapore). she has just returned to service after a lay-up at Venice of over a year and has been returned to top condition again.
The next KAZAKHSTAN-class likely to go for scrap is the ENCHANTED CAPRI (ex-AZERBAYDZHAN). She has been used as an accomodation vessel in a Mexican oil field in recent years and is apparently no longer needed now.