Well, yes - most of the limited reward levels are full. However, I would think that if someone wanted to pledge, say, $250 and the $250 level is full they would just pick a lower reward level and pledge over their reward instead of going for no reward at all. Unless of course none of the rewards below that level interested them, which I suppose is a possibility.
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So far, as I predicted, pretty much the whole $222 level seems to be made up of people who switched from the $192 level (or at least, the numbers add up rather closely - there's no way to know if it's the same people). The $575 level is really tempting me, but that's too much for me