So, I have been having correspondence from someone who has 3:16. They asked:

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>>>The aliens NEVER move on the range map.
>>>Only PCs move on the range map.
>
>Interesting. Why did you rule it like that?
>Any particular reason, metagaming -wise,
>why the aliens' counters don't move?
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Why did I rule it like that? Because it works and it's elegant is my answer.