Umbridge, dementors, spy in Order?

[Kirstini]

No: HPFGUIDX 72449

Caroline:
> Have searched in the archive, but can't find any reference to the
 fact that it  seems a bit of an amazing coincidence that the 
dementors turn up near Privet Drive just as Mundungus Fletcher hears 
about some dodgy cauldrons. 
Since Umbridge admits to sending the dementors, and since things 
aren't usually a coincidence in the HP universe, this suggests that 
she knew: a)  HP was being watched; b)  when Dung was on duty (unless 
she had ways lined up to distract any possible member of the order - 
but it does seem that Dung isn't known for his reliability).
So unless Umbridge is bugging the Order's HQ, presumably impossible
(from outside), how has she got this information? Is there a spy 
reporting to Fudge and/or LV?> 

Et moi (sorry, I'm feeling pretentious today):
Do we actually know that Fudge and Umbridge are aware of the Order? 
Molly and Arthur seem to have kept the fact that there was an 
official group formed from Percy, who does know that Sturgis Podmore 
was one of their/Dumbledore's associates, but doesn't appear to have 
a context to put that information in. Percy could, of course, simply 
be patronising Ron with an assumption that he doesn't know anything, 
but I feel sure that Arthur would have been fired from the Ministry 
if Fudge was aware of the full extent of his support for Dumbledore. 
The entire Order would have to be kept top secret, surely - as 
Snape's life would be even more at risk if Fudge and therefore Malfoy 
were aware of its existance. Obviously not just Snape, but as spy (?) 
he's more at risk than the others. This way, Umbridge wouldn't have 
known that Harry was being guarded - she wouldn't see any reason for 
him to need to be guarded anyway, as she supposedly didn't believe 
that Voldemort was back. Also, I think that Umbridge and all 
storylines directly connected with her are gone. She's wrapped up as 
much as anything was in OoP. Were that sort of revelation a-coming, 
JKR would have slipped it into the denoument of OoP rather than 
waiting for another book to wind up with. But yes, it is an annoying 
little coincidence. There were a few too many unexplained mysteries 
in OoP for my liking - just the little things which should have been 
concluded properly and weren't. Of course, I can't think of a single 
one just now.
Kirstini
PS: Welcome to the group, Caroline!