Does Sky stay after you restart IR?
Am witnessing constant erratic behavior with IR lately and this also happens among other things (+ shadow catcher turning black & objects disappearing, just because of simple changes as is phong tag angle, object soloing, editor visibility...), but at least IR baboon doesn't crash or attack... hahaha :)
Edit
Also, just found out HDRI textures applied to Sky objects are reverted (mirrored) on X axis (FIX: set X scale to -1).
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After rotating Sky object, shadow catcher keeps the projection from the camera. This can be observed only in active camera view. In viewport view (out-of-camera) shadow catcher shows as it should (is correct).