[thaumasiotes]

The scenario is not part of the new rule. Review Hijacking refers to transferring reviews from one product to an unrelated product, not transferring reviews from one product to the same product assembled on a different manufacturing line. The new version of the product may be obviously worse, but it is not a substantially different product.

[ceejayoz]

I've seen products get shitty enough in a subsequent production run to easily qualify as "substantially different".

The parent poster describes a chain of six free products. They're clearly not doing this as a charity exercise.