[Solved]-Highcharts - detect when render (or redraw) event is caused by a resize/reflow?-Highcharts

You can wrap the reflow method and call your alignment function after the process.

(function(H) {
    H.wrap(H.Chart.prototype, 'reflow', function(proceed) {
        proceed.apply(this, Array.prototype.slice.call(arguments, 1));
        console.log('after reflow');
    });
})(Highcharts);

Live demo: http://jsfiddle.net/BlackLabel/kc1zdg28/

Docs: https://www.highcharts.com/docs/extending-highcharts/extending-highcharts