Uncanny dodge = Immunity to feint?

[Infiniti2000]

How can you tell?
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How do we know which of these is room to move? None of them, apparently, are sufficient room for her to be able to move; has she, then, room to move?

Whether or not she's squeezing or bound seems to be the suggested metric by the rules. If you're not squeezing or bound, you have room to move.