Uno do not require you to take out line rental, nor is the broadband cheaper if you do. However, they do have cheaper line rental than some others.
LLU is used on their Fibre Pro and Fibre+ Pro packages, through the TalkTalk Business network, not Wholesale. It is also used on their Talk Surf packages, which as of present do not have a Fibre version, but that may be coming soon. This is an MPF solution, meaning your phone line and broadband are placed on the TTB network. The Talk Surf packages are significantly cheaper than their standard packages, so these are worth considering.