When adjusting a rotated GUI object’s anchor point the marker used to display it in the view port does not accurately represent where the anchor point truly is. The offset is applied correctly to the specified axes but the marker rotates with the image. It can be rather confusing to those who don’t know that this is the case.
I’ve added a gif to demonstrate this happening - the ImageLabel is rotated around its centre and the anchor point marker rotates around that point with it. *Edit - This is an AnchorPoint of ‘0, 0.5’.
An absolute bump from me, was looking for this exact point to be made. It makes no sense to have it rotate as if it was 0.5,0.5 when it’s been set to anything else. And as @EmeraldSlash mentioned, having a toggle for it as a new property would be a great compromise if anyone would disagree with this, although you could regain the same functionality by setting it to 0.5,0.5.