Edited!
Free refills are only for rewards members and only for drip coffee, hot tea and iced tea not including juice or lemonade, non rewards it is 50 cents though (plus tax)! The rule was only free/cheap refills as long as you're hanging out in the lobby (you can't come back later that day or the next day with an old cup or to a new store and expect a free refill). Although with Covid and not taking old cups or having the lobby open for you to sit, we've been more relaxed on the rules. My store has been allowing it if you come back through the drive thru or pop back in before you leave the area, whatevs!