The AA would expect you to become a member again before turning out and BT would expect you to become a BT Broadband customer again if you want to retain your legacy email.
As regards the second part of your post you should email the CEO of BT and ask him.
Hi @Jkseddon and thanks for posting.
I'm really sorry your email account has been deleted. @Keith_Beddoe is correct. Once you cancel your services you'll receive an email advising that if you wish to keep your current email address you need to sign up to premium mail. As you haven't done so the account will have been deleted and it's unlikely it will be possible to reactivate it again. How long ago was the account deleted?
Thanks for getting back @Jkseddon.
I can't make any promises but I'll take a look at this and see if there is anything that can be done. If that suits drop me over an email with the details. You'll get the contact the moderators link in my profile.