Thank you for your message. I have to leave Heathrow at 18:00 on November 21 (Friday). If possible, I would appreciate it if we could have a meeting at 13:00. Is it convenient for you?
I have to take a flight at 18:00 on November 11(Friday) to Heathrow. It will be glad if we could have a meeting at 13:00. Please let me know your schedule about that.
Please change "to Heathrow" to "from Heathrow". Thank you.