Jquery adapting scroller code

Hi,
I have the jquery below which is being used in a worpdres theme, to control one page scrolling.
I’d like to adapt it to meet the following condition only AFTER the page has scrolled…
if #id1 a OR #id2 a =“active” remove the class “active” from #id3
Hope this makes sense, many thanks for any help.
the jquery scrolling code is

/*-----------------------------------------------------------------------------------*/
/*    SCROLL EFFECTS & HEADER
/*-----------------------------------------------------------------------------------*/
jQuery(window).load(function($){
'use strict';
    /**
     * Page Loaded Stuff
     */
    jQuery('#page-loader').addClass('animated fadeOutDown');
    jQuery('body, html').addClass('window-loaded');
    jQuery('.light.scroller').animate({ 'opacity' : '1' });
   
    /**
     * Scroll Animations
     */
    jQuery('.animated').espy(function (entered, state) {
        var $this = jQuery(this);
        if (entered){
            $this.addClass( $this.attr('data-animation') );
        }
    });
   
    // Bind the event.
    jQuery(window).hashchange( function(){
        var url = location.hash;
        var minus = 64;
        if( jQuery('body').hasClass('admin-bar') )
            var minus = 96;
       
        if( url )
            jQuery("html, body").animate({ scrollTop: jQuery(url).offset().top - minus }, 500);
    });
   
    // Trigger the event (useful on page load).
    jQuery(window).hashchange();
   
    jQuery('#selectnav .scroller > a').click(function(){
        var $this = jQuery(this);
        jQuery('#selectnav .scroller').removeClass('active');
        $this.parent().addClass('active');
        jQuery('#selectnav .scroller a').removeClass('active');
        $this.addClass('active');
        history.pushState(null, null, $this.attr('href'));
        jQuery(window).hashchange();
        return false;
    });
   
    jQuery('a.scroller').click(function(){
        history.pushState(null, null, jQuery(this).attr('href'));
        jQuery(window).hashchange();
        return false;
    });
   
    jQuery(window).scroll(function(){
        var scrollTop = jQuery(window).scrollTop() / 12;
        var $header = jQuery('header#main-header');
        var $sub = jQuery('#selectnav ul');
       
        if( scrollTop < 20 ){
            $header.css({
                'padding-top' : 25 - scrollTop,
                'padding-bottom' : 25 - scrollTop
            });
            $sub.css({
                'padding-top' : 42 - scrollTop
            });
        } else {
            $header.css({
                'padding-top' : 5,
                'padding-bottom' : 5
            });
            $sub.css({
                'padding-top' : 22
            });
        }
       
        jQuery('#selectnav .scroller > a').each(function(){
            var scrollHref = jQuery(this).attr('href');
            if( jQuery(scrollHref).length > 0 ){
                if( jQuery(window).scrollTop() > jQuery(scrollHref).offset().top - 240 ) {
                    jQuery('#selectnav .scroller').removeClass('active');
                    jQuery(this).parent().addClass('active');
                   
                }
            }
        });
       
    });
});