In reply to a post by bet_here:

My phone line is due for renewal, with my broadband in-contract for another 6 months.
I was thinking about moving the phone to Zen now, with the broadband following later.

I would certainly take the Zen line rental now on a monthly minimum term and then assess the situation again in 6 months time. One thing to also bare in mind is that if you take Zen Unlimited Fibre 2 broadband only and you continue to have Zen line rental separately then there is apparently still no activation fee to pay for the broadband