Broadcast

The snippet below shows how to hook into the threewp_broadcast_get_user_writable_blogs action / filter to add access to a blog for a specific user.

/**
	@brief		Add access to a one or more blogs.
	@since		2018-12-13 14:18:17
**/
function my_threewp_broadcast_get_user_writable_blogs( $action )
{
 // We want to modify access only for a specific user.
 if ( $action->user_id != 1 )
  return;

 // And we want to add access to these blogs.
 $blog_ids = [ 51, 197 ];

 foreach( $blog_ids as $blog_id )
  $action->add_access( $blog_id );
}
// Broadcast fills the blog list at prio 100, so use a higher number.
add_action( 'threewp_broadcast_get_user_writable_blogs', 'my_threewp_broadcast_get_user_writable_blogs', 200 );