When a pricing page changes, what do you preserve besides the link?

Asks which fields make a changing pricing source reusable later.

A pricing page link is useful, but it may not show the same limit next month. I usually want the exact field, the date checked, and the decision that depended on it. Screenshots can help, but they can also hide region, login state, or billing term. When you cite a changing pricing page, what do you preserve besides the link?