[O] How do you use `pre-scheduled' deadline skipping with repeaters?

[Trevor Murphy]

I really like to use `pre-scheduled' as the value of 
`org-agenda-skip-deadline-prewarning-if-scheduled'.  Quoting the 
manual, "this can be used in a workflow where the first showing of 
the deadline will trigger you to schedule it, and then you don't 
want to be reminded of it because you will take care of it on the 
day when scheduled."

I started applying this to tasks with repeating deadlines.  So, 
for instance, I have the following in my agenda right now:

** REPEAT oil change 
  :drive:
SCHEDULED: <2014-12-23 Tue 09:00> DEADLINE: <2014-12-31 Wed .+6m>

When I mark this done, the deadline repeater updates as I expect. 
But the scheduling information stays there and I have to manually 
unschedule the task to get it out of my agenda.

I started looking into writing a function to unschedule after a 
repeat, but I'm having difficulty figuring out where to hook into 
`org-todo'.  Or do I want to hook into `org-auto-repeat-maybe'?

So, yeah.  Do others use this `pre-scheduled' workflow for 
repeating deadlines?  If so, is there an obvious solution to this 
little nuisance that I'm not seeing?
--
Trevor Murphy, ASA, MAAA
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