Note that this policy is only for new series. If the "etc." series has already been established that way do not bother to change it over to the new format.
Example:
Bede, the Venerable, Saint, 673-735. [Works. 1955] Bedae Venerabilis Opera. -- Turnholti : Brepols, 1955- v. ; 26 cm. -- (Corpus Christianorum. Series Latina ; 118A, etc.) BR 60 C49 V.118A BOOKSTACKS(BOOK) BR 60 C49 V.119 BOOKSTACKS(BOOK) BR 60 C49 V.119A BOOKSTACKS(BOOK) BR 60 C49 V.120 BOOKSTACKS(BOOK) BR 60 C49 V.122 BOOKSTACKS(BOOK) BR 60 C49 V.123A BOOKSTACKS(BOOK) BR 60 C49 V.123B BOOKSTACKS(BOOK) BR 60 C49 V.123C BOOKSTACKS(BOOK)NOT:
BR 60 C49 V.118A, etc. PT.I BOOKSTACKS(BOOK)
BR 60 C49 V.118A, etc. PT.II, 2B BOOKSTACKS(BOOK)
BR 60 C49 V.118A, etc. PT.II, 1 BOOKSTACKS(BOOK)
BR 60 C49 V.118A, etc. PT.II, 4 BOOKSTACKS(BOOK)
and so on...