Ultimate Member - Change date format to timestamp

Ultimate Member - Change date format to timestamp

<?php
add_filter('um_user_pre_updating_profile_array','um_custom_user_pre_updating_profile_array');
function um_custom_user_pre_updating_profile_array( $arr ){
	global $ultimatemember;

	foreach ($arr as $key => $value) {
		$field = $ultimatemember->fields->get_field( $key );
		if( $field['type'] == 'date' && ! empty( $value ) ){
			$arr[ $key ] = strtotime( $value ); 
		}
	}
	return $arr;
}

add_action('init','um_custom_init');
function um_custom_init(){
	remove_filter('um_profile_field_filter_hook__date', 'um_profile_field_filter_hook__date', 99 );
}

add_filter('um_profile_field_filter_hook__date','um_custom_profile_field_filter_hook__date', 100, 2 );
function um_custom_profile_field_filter_hook__date( $value, $data  ){
	global $ultimatemember;
		
		if( is_numeric( $value ) && ! strstr( $value , "/" ) ){
				$value = date('Y-m-d', $value );
		}

		if ( $data['pretty_format'] == 1 ) {
			$value = $ultimatemember->datetime->get_age( $value );
		} else {
			$value = $ultimatemember->datetime->format( $value, $data['format'] );
		}

		return $value;
}

add_filter('um_edit_date_field_value','um_custom_edit_date_field_value', 10, 2);
function um_custom_edit_date_field_value( $value, $key ){
	$value = date('Y-m-d', $value );
			
	return $value;
}
?>