According https://docs.ogc.org/is/19-086r6/19-086r6.html#_8f4c9f38-bc6a-4b98-8fd9-772e42d60ab2 extent.temporal.values is mandatory but what is published in v1.1 schema says that it is not (also current version). I think in this case schema is correct and it should be fixed in documentation.