Prices and limits live in one curated file. Each figure is stored with the address it was read at and the date. When a figure changes, the edit adds an entry here with the old and the new value, so the history of that file is the history of the plans.
Nothing is rewritten automatically from a scrape. Pricing pages change layout often and rarely publish limits in a structured way, so a script that copies numbers would be wrong without anyone noticing. The scheduled job only answers one question: did the visible text of the page change since last week?
What you will not find here
Changes from before the first snapshot, and limits reported on forums. Both exist elsewhere, and both are hard to verify. A figure unchecked for more than 30 days is flagged wherever it appears on this site.