Moving house, porting landline to FTTP

[AnnieMouse]

Hullo all!
My partner has a business landline at his flat (probably copper, possibly FTTC)

He will eventually be moving in with me, and will need to keep a landline - ideally the same number for ease of continuity.
However, I've got FTTP from TalkTalk which, although amazing, doesn't come with a landline.

What can we do/what's the least hassle to ensure he can smoothly transition to having his business at my address? 

[licquorice · Accepted solution]

This is the BT residential forum, you need to post on the business forum. https://business.forums.bt.com/

I suspect it will involve moving his business line to your premises as a second line.