Moving broadband 3".

[#1]

For various reasons which seemed good at the time, I have two plusnet broadband accounts.
These are connected to two BT lines, with sockets right next to each other.
I'm unsure how to go about what I want - any pointers would be appreciated.
Ideally, I'd like to simply swap my 'main' line onto my 'alternate' line - including phone number
and broadband account, then cease the alternate line.
My main line has plusnet premier with 80G, and I'd prefer this to move, rather than starting a new
plusnet extra service.
Is this possible?
If not, a second-best option would be to just move the broadband account, and forget keeping the number.
Is there any way of simplifying this rather than going through the whole 'so you're moving home'
process?
If I'm willing to sign up to plusnet phone on the line I'm moving my main account to, does this change anything?
Or would other alternatives - such as upgrading the alternate line to plusnet extra, deleting the main account, and
changing the name of the account so that email doesn't bounce work?
Thanks, and sorry for the confused questions.

[#2]

Hi SpeedEvil,
On the line that you want it transferring to, is that plusnet phone line rental or a BT one? If you were to move your account and phone number over to the other line it would indeed have to be classed as a house move. We would, however, defer that £65 charge unless you were to leave within 12 months.
Jojo

[#3]

They're both BT lines.
Interesting, thanks!