My order says Completed, when will I receive it?

I have received an email from Harts Nursery to say my order has been completed. What does that mean and when I can expect my order to be delivered?

Hi there,
Once we have packaged your lily bulbs, you will receive a notification from us by email to say your order is Complete. We will then send your lily bulbs by Royal Mail on a tracked 48hour delivery service. Once your parcel is in the hands of the Royal Mail, you should then receive an email or text message (depending on the information you gave when ordering with us) from them to confirm the estimated delivery day/time.
You can also track your parcel with the Royal Mail at:
using your consignment number.

Many thanks
Loraine Hart