Your address does not change
Connect the mailbox you already have. Nothing moves, and there is no new address to learn.
Alternatives
BT Email has carried btinternet.com addresses for a long time, along with the older btopenworld.com and talk21.com ones. If one of them is yours, you can keep it. Patriot Mail opens your BT mail in a calm inbox that is easy to read, and your mail stays with BT.
Your btinternet.com address stays exactly as it is, and so do the older btopenworld.com and talk21.com addresses. Patriot Mail connects the BT mailbox you already have, with nothing to move.
BT asks every email app for an app password rather than your own. You create one in your BT account, paste it into Patriot Mail once, and your usual password keeps working on the BT website.
Block a sender, or a whole company by blocking its domain, as many as you like at no charge. Mail from them is usually deleted as it lands, and otherwise the next time you open the app. Unsubscribe from newsletters in one tap.
Patriot Mail is free, with no subscription and no trial that ends. Your messages are not permanently stored on Patriot Mail servers, and your inbox data is not sold or used for advertising.
Yes. They are BT mailboxes, and they connect the same way as a btinternet.com address.
BT asks for an app password, which you create in your BT account. Your own password keeps working on the BT website.
Yes. It is free to use, with no subscription and no trial that ends.
Ready when you are
Connect the mailbox you already use and get a calmer inbox in about a minute. Free, with no subscription, and the address you have had for years stays exactly where it is.