If a language has both SOV in a full sentence and determining N+determined N in a Noun Phrase, then it has at least some postpositions, which historically come either from verbs (ex. Bengali), or from nouns (ex. Mande languages (W. Africa)).
Standardized
IF basic order is SOV and determining elements precede determined elements in noun phrases, THEN there will be at least some postpositions, which historically derive either from verbs or from nouns.
Cf. relevant Greenberg universals, which are presented as being achronic, though.