Truth be told they really don't have to honor the price difference, except you would need to replace the orders.
Our price protection does not cover:
Non-HP branded products
Business series products (including Zbook, Elite, Pro, workstations, thin clients and servers)
Special promotions including financing offers, bundle offers, free items, pricing errors, mail-in offers, coupon offers, items that are advertised as limited-time-only (lightning deals) or limited quantity, out of stock items, clearance items, credit card offers, gift card offers, and items for sale from Thanksgiving Day through the week following Thanksgiving