I have seen this sort of thing in the past, particularly when the mount has tracked past the meridian. If you run with no scope it's possible to let the mount run indefinitely and I've seen it get to the expected position having rotated through almost 360 degrees. Usually the alignment has been destroyed though. Also seen pier flips via the South pole instead of the North.

One thing in this case is that the declination is negative and perhaps that makes a difference. Perhaps the mount is trying to get to -8 deg by going the long way round, via +90, 180, 270/-90.

One thing that may help is an earlier HC firmware version. - or use the NexStar+ HC rather than the StarSense. The StarSense implements sync is a different way,

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