"The Boy Who Cried Wolf" factor
Whether it's a coincidence or not with the timing of the alerts, I dunno. If I were an evil minion in the admin seeking to manipulate the elctorate via terror alerts, I'd be careful about piling them on top of each other. They eventually just become background noise, about as effective at swinging the voter's intentions as the sound of their own breathing.
That of course doesn't mean that we aren't being manipulated. Skepticism can be a helpful thing...evidence even moreso, though. (And yes, I do see the irony of using the word "evidence" in defense of this admin.)