Be aware with TalkTalk they will want to provide full LLU (MPF)
Have a read of this from another site's forum.
There's a heck of a lot of rot in that linked thread.
There can be difficulties getting back from TT LLU, but not only BT
are supposed to be able to do it without loss of service, (sometimes failing and sometimes because of staff ignorance don't even know). Also Plusnet, (as stated in that thread though mistakenly at first as being LLU), the fact they are owned by BT being irrelevant as all internal systems are completely different, and I wouldn't be surprised if vivaciti and perhaps Xilo/uno can manage it as well.
However for some reason transfers back from TT and Sky often seem to leave the user without broadband for days or even weeks. Getting back from Sky full LLU seems to be a bit safer these days than from TT, but that's just hearsay from what I see on these forums.
As for engineers needing to visit the exchange, that is a complete red herring as it is required for partial LLU as well. All ADSLx broadband supply
requires the line from the user to arrive at the CP's MSAN or DSLAM at the exchange, (BT Wholesale being the underlying CP for non-LLU), where for partial LLU the phone connection is split off to go to the main distribution frame and for full LLU is I believe handled by the ISP's backhaul.
In short - for non-LLU the line terminates at a BT Wholesale MSAN/DSLAM; for partial LLU such as O2/Be and a few legacy Sky connections it goes to the O2/Be or Sky DSLAM respectively; and for full LLU it goes to the CP's DSLAM.
All migrations to and from either sort of LLU require an engineer visit to the exchange. The only case I'm not sure of is migrations between an LLU ISP and resellers using that ISP's DSLAM to provide LLU services.
My broadband basic info/help site - www.robertos.me.uk
Domains,website and mail hosting - Tsohost
. Connection - Plusnet
Extra Fibre (FTTC). Sync ~ 56.0/13.9Mbps @ 600m.
"Where talent is a dwarf, self-esteem is a giant."
- Jean-Antoine Petit-Senn.
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