I guess it is always possible that I screwed up and sent a blond ale, but I don't see how. The IPA was bottled and labeled on a different day than I bottled the blond ale and I am not a bottle short of the blond ale. Plus the two didn't get switched since the blond did well with comments fitting the beer.
Just because the blonde got judged properly doesn't mean they weren't switched. Just last night, we had judges pour out an IPA that wasn't. I had them pop the second bottle, and it was the IPA. I did some digging, and it turns out this guy had also entered an English Brown. However, one of the beers got mixed up, so his two bottles in the IPA box were a brown and an IPA, and the same thing in the brown box. So depending on random chance, if this kind of error is made one beer may get judged just fine while the other is the mixed up beer. Thankfully for us, the brown and the IPA were sufficiently distant categories that the judges immediately knew something was wrong and we could get both beers judged properly (it helps being able to look at the bottle and distinguish the beers).
Keep in mind this kind of error could be your fault, or it could be the competition's. No way to tell. We all try our best, but don't claim to be perfect.