WordPress at a glance
filter is not described

get_lastpostmodified filter-hook . WP 2.3.0

Filters the most recent time that a post was modified.

Usage

add_filter( 'get_lastpostmodified', 'filter_function_name_6438', 10, 2 );
function filter_function_name_6438( $lastpostmodified, $timezone ){
	// filter...

	return $lastpostmodified;
}
$lastpostmodified(string/false)
The most recent time that a post was modified, in 'Y-m-d H:i:s' format. False on failure.
$timezone(string)
Location to use for getting the post modified date. See get_lastpostdate() for accepted $timezone values.

Changelog

Since 2.3.0 Introduced.

Where the hook is called

get_lastpostmodified()
get_lastpostmodified
wp-includes/post.php 6454
return apply_filters( 'get_lastpostmodified', $lastpostmodified, $timezone );

Where the hook is used (in WP core)

Usage not found!