Sorry to jump on this thread but I have had terrible issues logging into my master email account.
Have had to change the password 6 times and eventually been able to log back in. Liaised with BT over chat and the phone and whilst I can now get back in, I am concerned that some changes have been made without my authorisation.
When I log in via bt.com/mail I now see a Yahoo holding page. Never saw this before. Further, I can't find a way to manage the linked sub accounts. Some time ago one of the mods correctly linked our premium email accounts to my home broadband account so I didn't pay extra for the email. I wonder if one of your BT colleagues has played around with this?