Apple AC Wall Plug Adapter Exchange Program

So, I checked online and my 3 phones' adapters were eligible for replacement.

Based on the instructions here - I have 3 options:

Exchange Process

Please choose one of the following options below. We will need to verify your Mac, iPad, iPhone or iPod serial number as part of the exchange process so please find your serial number in advance. Finding your device serial number is easy.

• Exchange your adapter(s) at your local Apple Store or an Authorized Apple Service Provider.
• Request a replacement via the web.
• Contact Apple Support.

So I chose to request a replacement via the web.

Upon completion of the required steps, I was told to "Please take your (phone) and the label below to any (post office)" - and that I should not any other items.

However, there was no label available to print or download.

And it was not clear if I should return the small adapter that would be replaced.

I tried getting in touch with Apple Support but there's no option to inquire about the proper process. And since my phones are OOW, it would cost me around $40 to make that inquiry.

So - perhaps someone here could assist.

Do we need to mail in the part that is to be replaced?

Could someone clarify the steps further?