Fix invoice_to for next billing period

app/Models/Service.php

@@ -265,7 +265,7 @@ class Service extends Model
 	{
 		$query = $this->hasMany(InvoiceItem::class)
 			->where('item_type','=',0)
-			->orderBy('date_orig');
+			->orderBy('date_start');
 
 		if ($active)
 			$query->where('active','=',TRUE);