A test is a snapshot under the conditions described in the report. The product, market, standards, comparison group or methodology may change between the test and the advertisement. That does not automatically make the result useless, but the advertising must make clear which temporal and factual status it represents.
Currentness matters especially where the advertisement uses terms such as “current”, “new”, “today” or a present-tense leading position. A dated result can support such a statement only where the time context is clear and later changes are not concealed. An old report must not silently appear to be a new investigation.
The file should therefore include the test date, report publication date, products compared, product status at the time of advertising and any later changes. For dynamic products, record whether software updates, formulation changes or new production series affect the properties examined in the test.