How a row changes, and what the dates mean

1Two dates, because they answer different questions

The first says when this value started being true as far as this record knows. The second says when somebody last opened the vendor's page and checked. A field can be years old and checked yesterday, or written last week and never looked at since.

Most records carry one date and leave the reader to guess which of those it means. On a subject where vendors change plan tables quietly, the second date is usually the one that matters, and it is the one a single date almost never is.

2Confirming an unchanged value still counts as work

Re-reading a page and finding it identical advances the check date and nothing else. That is the most common outcome of a review and it is worth recording, because the alternative is a record where old and verified look the same as old and forgotten.

Page dates behave differently: they move only when the content actually changes. A page whose date has not moved has not been edited, which is a different claim from nobody has looked at it.

3What a stale row looks like from outside

The failure mode worth guarding against is a field that is quietly wrong: a plan price moved, a feature line was renamed, and the record still shows last quarter's reading with no signal that anything happened. Nothing about the page looks different when that is the case.

The check date is the only defence, which is why it sits on every field rather than once at the bottom of the page. A reader who finds a check date older than they are comfortable with can open the source link in the same row and settle it in a minute.

4When a vendor changes something, the row is rewritten, not annotated

The current value is what the field holds. There is no running history of previous plan prices or previous wordings, because maintaining one accurately across six vendors is more work than this record can honestly promise, and a half-maintained history is worse than none.

What does persist is the pair of dates, which is enough to tell a reader how fresh the current value is without implying a completeness the record does not have.

5Sources

The pages each field is read from are listed on the support table, with a date on every row. The rest of the method is on the protocol page, and the companion note is what earns a row.