took me a while, why I would always get the wrong address.
Im using commerce Kickstart
Steps to reproduce:
go to checkout
select pre-existing address for shipping (if default address is set, this is automatically filled)
finish the order.
Now the saved address is the selected pre-existing one, ignoring the changes.
It seems the shipping address is the same as the billing address now, even weirder.
I would assume, it would use the changed address or the fields should be disabled, once an address is selected.