Trade-in box

Dear community members,

I have placed an order for a new iPhone with a trade-in for my existing iPhone. I received confirmation that a shipping box will be sent to me and I have to send the existing phone within 14 days. However, my new iPhone will be delivered 30 days from the date of purchase.

As I need to transfer data from the existing one to a new phone, can I send the trade-in phone after receiving the new one?

Thanks!