Do not overwrite the past
A state or authority change can leave earlier identifiers relevant for older records. Keeping an original code avoids incorrectly assigning a modern location simply because the digits look familiar.
Evidence for a transition
A useful relationship needs an official source and dates showing what changed. Treat prefix changes, office reorganisations and renamed cities as separate events. This dataset has not completed a national history table; unknown relationships remain unresolved.
Why an old official page is not enough
Nagaland’s reference reproduces a notification taking effect in 1989, but its embedded state-code table is unavailable. It is not a complete current or historical transition register. We therefore do not derive a national replacement table from it.
Review scope
- National transition table incomplete; reviewed state-code pages mix historical and newer entries and contain inconsistencies.
Official references and unresolved checks
- Nagaland MVD — historical registration-mark notification
Historic notification explanation only. Embedded state table unavailable; colour text not used as a current rule.
- Telangana Transport — state-code reference
Mixed-era reference; PN for Punjab and historical rows make it unsuitable as an unqualified national master list.