We have modified the GraphQL Delivery API to allow users filtering on the system properties of an entry or asset via comparison filters.

The firstPublishedAt, publishedAt and publishedVersion properties now support comparison filters:

• <sys property>_gt - greater than the argument value
• <sys property>_gte- greater than or equal to the argument value
• <sys property>_lt - lower than the argument value
• <sys property>_lte - lower than or equal to the argument value

The following string type filters were non-functional and have been removed from the SysFilter input type:

• firstPublishedAt_contains
• firstPublishedAt_not_contains
• publishedAt_contains
• publishedAt_not_contains
• publishedVersion_contains
• publishedVersion_not_contains

You can read more about GraphQL collection filters in our Developer docs.