Changing broadband line

[c1223]

I currently have two incoming lines. One has a phone line, the other has a fax line & broadband. I now want to get rid of the fax line but keep the broadband. There's two options I guess:

1) Get the fax line turned into the phone line, and then risk having the number transferred from the phone line to the fax line. Supposedly there is a minimal risk of losing the number

2) Get the fax line and broadband line shutdown and have broadband set up on the phone line.

Obviously option 2 is the desired option HOWEVER we currently run our broadband from one of those infinity master sockets using the Openreach white modem connected to our own router/networking devices. As far as I'm aware, with the new setups, they just send you a Homehub 5 and that will work connected straight to whatever socket you already have installed. However, I'd very much prefer not to use that for various reasons. 

So, will it be possible to move the inifinity face plate from my current broadband line to the new broadband line and use my white modem?

[licquorice]

Yes, you don't have to use the Homehub, you can continue to use the modem and router.

[c1223]

Supposedly it is "against the T&Cs" to mess with the face plate? Presumably they won't know if I do it (as long as I don't break anything).

[licquorice]

The simplest answer (but probably very complicated for BT systems to cope with) is to cease number x (fax number) on line A and then move number y (phone number) from line B to line A. The systems probably won't be able to cope with ceasing the fax line without also ceasing the broadband though.

[c1223]

Ceasing the broadband line isn't the problem. We can do without the broadband for an extended period of time. What we absolutely can't lose is our phone number on "line B" when trying to move it.