[Orgmode] changing the time of one instance of a recurring appointment

[Erik Iverson]

Hello,

I did not see this addressed in the manual or FAQ.

Say I have a recurring appointment, every third Monday of the month, at 
11:30 AM, no problem:

** Monthly meeting with Boss <%%(diary-float t 1 3)>11:30

Now, my boss emails me and says, let's change next week's meeting to 
10:30.  How would you handle that?  Just simply change the 11:30 to 
10:30 and remember to change it back next week?  Add a new one-off 
appointment for 10:30 that day and ignore the 11:30 one on your agenda? 
 Or is there some way to do this built into org-mode already?

Thanks a lot!
Erik Iverson