subscription ->service() ->calculateUpgradePrice($recurring_invoice, $target); /** * Null value here is a proxy for * denying the user a change plan option */ if (is_null($amount)) { render('subscriptions.denied'); } return render('subscriptions.switch', [ 'subscription' => $recurring_invoice->subscription, 'recurring_invoice' => $recurring_invoice, 'target' => $target, 'amount' => $amount, ]); } }