There is no special charge for moving from O2 LLU. I don't think there is from any LLU.
Both O2 phone and Plusnet phone are "Wholesale Line Rental" from Openreach. The O2 one is not LLU even though your broadband is. That may be where the charging confusion about LLU arises. It should be a simple billing change like when/if you change your electricity supplier.
Plusnet Fibre and Phone bundles currently have free installation, see
this page. Plusnet Fibre has a £50 installation charge if you don't take Plusnet phone.
I'm not actually sure if you fully understood my original question, as I assumed you have your line rental with O2, without asking if I was correct. Do you?
Because if it is with O2, unless things have changed you have to move it away within a short period after migrating the broadband away. So you may as well put it with PN to avoid the fibre installation charge.
It's also worth looking at the Quidco and TopCashBack cashback sites and seeing what is there for Plusnet. If you decide to go ahead, make sure you either clear cookies before going in to order through the cashback site, or us a different browser that has never been used to look at Plusnet. (Some people keep a browser especially for cashback sites, so they can happily clear cookies without losing the ones they find useful in the normal browser).
My broadband basic info/help site - www.robertos.me.uk
My domains,website and mail hosting - Tsohost.
Internet connection - Plusnet Value Fibre FTTC 80/20 trial.
"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
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