Hi and

to nthw!
You are correct that the password for the webspace will not change with the primary email address, and it will be the original password.
The contact us form has now replaced any email contact.
To get the username and password, you don't have to speak to technical support, if you call customer services they will be able to confirm these details for you, either 151 from an ntl phone, or 0800 052 2000... freephone
hope that helps