When you arrive with a discount code in the link, the price you will pay now appears on the plan card itself, next to the regular price with a line through it, and the renewal price sits beside it. Before, the campaign price was only shown in a note above the plans, so the card underneath still read the full price.
The checkout summary also had its discount line wrong: it repeated the plan price instead of the amount being taken off, so the three figures did not add up. It now shows the discount itself. Nothing about what is charged has changed - the amount due today was always correct.