When did Fudge change his mind?

[c_robocker]

No: HPFGUIDX 92570

Elihu wrote:
Fudge's reaction to the possibility of LV's return was expected by 
Dumbledore, but seems to go against something he said in PA10: "I 
must say, You-Know-Who alone and friendless is one thing...but give 
him back his most devoted servant [meaning Black], and I shudder to 
think how quickly he'll rise again...."
  
18 months later, when Dumbledore mentions LV's return to power, and 
Black still out, he says "You-Know-Who returns? Preposterous. Come 
now, Dumbledore..."[GF36] And when Umbridge brings Harry to 
Dumbledore after the DA was almost caught, Fudge says "Or is there 
the usual simple explanation involving a reversal of time, a dead 
man [Voldemort] coming back to life, and a couple of invisible 
dementors?", each of those being considered impossible.
 
When did Fudge change his mind?

CRobo writes:

That's one of the reasons I love these books and find this group so 
interesting.  In the last few messages this morning, someone has 
understood them to mean something that I did not (ref Hand of Glory 
post) - but either could be correct!

I read this one as sarcasm from Fudge.

CRobo