Keeping Plusnet email address after moving to BT

[#1]

Can I keep my Plusnet email boxes after moving to BT [to get access to the Fon network]?

[#2]

You will need to pay for it http://www.plus.net/support/service/policies/cancellation.shtml#generalPolicies

Quote

It is possible, when requesting an account cancellation, to request a downgrade to a mail only package for £20 a year instead of full account closure. This will allow continued access to email and some member centre features. This option must be requested at the time of cancellation.

[#3]

Once upon a time it was free if you knew the right question to ask.  
(Though that may only have been possible if, like me, you had active referrals - I've kept mine since 2008 despite having been elsewhere for a fair bit of the intervening time)

[#4]

Thanks for this. I did ask Jess the Robot before coming here but it failed to understand my query, which was something like 'can I keep my email address if I move to BT?'.
The way Jess comes up at the top of the screen when looking for or at 'Policies' makes it easy to not find them. Less Jess more Contents pages would be better.
The key words, evidently, are 'cancellation', 'migration' and 'policies'. None of which occurred to me. Live and learn!