Hey comrade, im sure the plants will swell a little more up to a point. But remember those trichs that go from clear, milky to amber? an overripe plant will have degraded trichs past their optimal point meaning the quality will be lowered. Also, they might hermie & develop seeds if left too long.
If you watch some completed grows by pro growers like TaNg buds are growing big through entire grow. Keep them flowering until say 80-90% pistils are amber. After that you can't gain much by keeping them in flowering mode.