Hi,
Points are indeed not updated if you modify the order after its creation. I totally agree with you that the points should be updated in such a case.
That's a capability we could add in the future but it's a lot of work as the system doesn't know why the points were attributed.
For example, in the settings of the points plugin, you can configure points to be gained based on the amount of products in different categories. So if I then delete a product from an order, it would mean that I would have to remove points from the user if the product is in a category listed in the plugin. But right now, the information of the points is stored only global to the whole order. So I don't really know how much points to remove. I could try to calculate it based on the settings of the plugin, but the settings could have been changed between the order creation and the removal of the product. So it would require storing the points for each product when the order is created. But then if the points given are global to the order (like if you give points based on the user group of the user) then the points can't be for each product. So that means that there also need to be that information saved for the whole order.
And we still want to know the global amount of points. So it needs some kind of synchronization between the points of each product, the points global to the order and the total number of points gained / lost by the order.
What I'm trying to say is that a lot of work will be required for that to work properly and take into account all the different ways points can be configured while the gain is only a few seconds to not have to manually update the points of the user when an order is modified (other than changing its status), which normally doesn't happen that often. And that's why it's on the back-burner for now.