that would depend on the charger, if it's one of our intelligent multi stage chargers it would continue on different cycles to get the best out of your battery, if you have put them on old batteries for the first charge might be wise to leave them overnight.
You could try unplugging in leave a minute or so and plugging it back in you will probably find its green, then after period will go back to red as it attempts to try a different level of charge to get the best it can from the cells.