We really don't want you to miss out on anything that you have ordered, so sometimes we fill orders from multiple warehouses which may result in separate deliveries.
If that is the case, then you will receive two separate invoices with _1 and _2 at the end denoting that they are a split order.
Rest assured, in the case that your order is dispatched from more than one warehouse, you will, of course, receive the corresponding tracking numbers.
Please note, delivery times may vary depending on where your product has been shipped from.
You can find out more about delivery times here.