There is a bit of debate about how to translate πολίτευμα in Philippians 3:20. In modern commentaries, the translation ‘citizenship’ is usually rejected because of its weak attestation in ancient texts.
The problem I see with translating πολίτευμα as ‘civic association’ is that, in English, it is quite an un-intuitive phrase. Any perceived ‘governance’ by a ‘civic association’ would be, at most, minimal.