my drop cable splits into two wires - is this normal/ok?

[#1]

And do Plusnet quote people the B range of speeds in case they have unfiltered extension sockets? I don't think you do. Your "rare exceptions" are anyone who has more than one phone socket and lacks a centralised filter.

[#2]

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@MattyC wrote:

In some instances, we recommend checking with local electricians to see if they could arrange things for you. A new NTE5 master socket would probably improve the experience.

I certainly would not recommend this approach @MattyC.   Electricians generally have limited experience of Telecomms wiring apart from connecting wires between points.  Seen a number of jobs completed with straight multi-core not proper twisted pair - OK it normally works for the phone, but ADSL / FTTC?  Much better to look in the local small ads for an ex(?)  BT man who will do a much more reliable job.

[#3]

Just a final thank you to those who offered their comments. It's been helpful and my options are clearer now.

nox