If 'VACCINES' is coded as ’RDYYLJHO’, 'PROJECT' is coded as LNRFHYP’, then how is 'STARDUST' coded as?

The logic followed here is, vowels are replaced by their 3rd succeeding alphabet as per English alphabetical series and consonants are replaced by their 4th preceding alphabet as per English alphabetical series. In VACCINES: V         A         C         C         I           N         E         S -4         +3        -4         -4         +3        -4         +3        -4 R         D         Y         Y         L          J          H         O Code for ‘VACCINES’ is ‘RDYYLJHO’ In PROJECT: P         R         O         J          E         C         T -4         -4         +3        -4         +3        -4         -4 L          N         R         F          H         Y         P Code for ‘PROJECT’ is ‘LNRFHYP’ In STARDUST: S         T          A         R         D         U         S         T -4         -4         +3        -4         -4         +3        -4         -4 O         P         D         N         Z          X         O         P Code for ‘STARDUST’ is ‘OPDNZXOP’