Events Calendar 3.6 // Customize 'Event has Passed' notice

gistfile1.php

add_filter( 'tribe_events_the_notices', 'customize_notice', 10, 2 );
function customize_notice( $html, $notices ) {
	//If text is found in notice, then replace it
	if( stristr( $html, 'This event has passed.' ) ) {
		//Customize the message as needed
		$html = str_replace( 'This event has passed.', 'This event has passed and <a href="">add a link</a>.', $html );
	}

	return $html;
}