Leaving a day early

Shadow Harry first. He's polite but counting money, so let "Ouch" and "Hmm" carry real feeling; they tell the agent more than a full sentence would. Then take the agent's part. Her lines are clear and patient, with the numbers spoken slowly: "one hundred and fifty", "sixty".

1. AgentReservations line, this is Kim speaking. Are you changing a booking?
2. HarryYes, please. My flight from Shanghai to London. My meetings finished a day early.
3. AgentLucky you. Can I have your name and travel date, please?
4. HarryHarry Williams, flying this Friday night.
5. AgentThank you, Mr. Williams. You're on Friday's flight at eleven p.m. When would you like to leave?
6. HarryThursday night, same time, if there's anything.
7. AgentLet me check. There are seats, but your ticket has a change fee of one hundred and fifty dollars.
8. HarryOuch. Is that the only charge?
9. AgentThere's also a fare difference of sixty dollars, because Thursday is busier.
10. HarrySo two hundred and ten dollars to go home one day early. Hmm.
11. AgentThere's another option. You can come to the airport and try standby for Thursday's flight.
12. HarryWhat does standby cost?
13. AgentOn your ticket, nothing. But you only get a seat if one is free at the gate.
14. HarryAnd if there isn't one?
15. AgentYou keep your Friday seat and fly the next night, as planned.
16. HarrySo the worst case is a wasted evening at the airport. Let's try standby.
17. AgentGood choice. I've added you to the list. Get to the gate early; the list goes in order.
18. HarryPerfect. Thanks for mentioning it. I wouldn't have known to ask.
19. AgentYou're welcome. Have a safe trip, Mr. Williams.