Recent generations of my avi impostor have the head offset to one side that did not previously happen.
This model has a gimmick where it can remove its head by constraining the bone to the left hand, and it _looks_ like the impostor is being generated with that constraint at half weight even though it's _never_ set to half weight in unity.
(the floating discs are a different unrelated older issue)
Images in order
Broken impostor
Model the broken impostor is generating from
Older functional impostor on a similar model
Model that older impostor was generated from

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