Product Discounts not re-calculating if products removed from cart (store v2.0)

Hi there,

I have a question on Product Discounts as described in the 2.0 documentation:

I'm generating the discount form code fine and the bulk discounts are applying properly, however, in a situation such as:

1) I have a bulk percentage discount on all units that applies a 10% discount on 5 or more products.
2) The user adds a quantity of 4 items to their cart.
3) The user then adds a quantity of 1 (of the same product) to their cart. This essentially gets them to the 10% discount.
4) The user then removes the cart item with the quantity of 4.

Should the cart then re-check the bulk discount and remove the 10% discount on the single product left in the cart? If I proceed to checkout it also keeps the 10% discount on the single product. Am I missing a step or not configuring something properly or could this be a bug?

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