Mrs. van Andel,

I am very sorry, but I need to reschedule your appointment for tomorrow, July first, at three. At this moment, I am uncertain when I'll be able to see you. If you'd rather make other arrangements, I understand. I will owl you when I know for certain when I'll be able to reschedule you to.

I am very sorry for any inconvenience this may cause you.

Sincerely,
Ginevra Weasley
CHoB