I think only this offer terminated the trick. D2H might have updated all customers pack who have HD add-ons.
Their intention should have been remove the offer priced HD add-ons and update it with the regular HD add-ons of the respective base pack.
But instead of identifying the customers who have the offer priced HD add-on, they simply identified all the customers who is having HD add-ons and updated the pack with the HD add-on of the respective pack.
This is my assumption and it is fitting for the current scenario as well.
If someone interested, you can try the trick once again. Or if someone already tried, let us know if it is still working or not.
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