$bankHolidays = array();
foreach($obj as $e) {
    if($e->division == 'england-and-wales') {
        foreach($e->events as $events) {
            $bankHolidays[] = $events->date;
        }
    }
}

$ret = date('d-m-Y', strtotime($bill["charge_customer_at"]. ' +2 weekdays'));

$date = '2017-07-25';
$reserved = ['2017-07-27', '2017-07-28'];
$days = 2;

while ($days > 0) {
    $date = date('Y-m-d', strtotime($date . ' +1 weekday'));
    if (! in_array($date, $reserved)) $days--;
}

var_dump($date);

function nextBusinessDay($date, $daysToSkip,$holidays){
    $day = date('Y-m-d',strtotime($date. ' + '.$daysToSkip.' weekday'));
    if(!in_array($day,$holidays)){
         return $day;
    } else {
        return nextBusinessDay(date('Y-m-d',strtotime($date.' +1 day')), $daysToSkip,$holidays);
    }
}

$date = '2017-07-19';
$holidays = ['2017-07-21'];
echo nextBusinessDay($date,2,$holidays);//returns 2017-07-24

$date = '2017-07-19';
$holidays = ['2017-07-21', '2017-07-24'];
echo nextBusinessDay($date,2,$holidays);//returns 2017-07-25 like if it were a 4 day weekend

return nextBusinessDay(date('Y-m-d',strtotime($date.' +1 day')), $daysToSkip,$holidays);

return nextBusinessDay(date('Y-m-d',strtotime($date.' +'.$daysToSkip.' day')), $daysToSkip,$holidays);