Just find out that if you had civic osmosis from congress and you agreed to take the new civic, then nothing stops you to cancel it and retake previous one on that turn.
So maybe it would be better if congress not only provided osmosis but also banned the other variant for all, except who refused and paid influence. The ban may be permanent (until next session on this law) or for 20 turns, or until the end of next session

Or change it basic cost to the osmosis refusal cost