Line Fault fixed, both u/l & d/l are worse than before the fault occured.

[#1]

Not sure whether DLM hasn't been reset?  or there is an underlying issue as a result of being attached to a spare pair.

According to BT Broadband Availability checker I should get between 64.1 & 80mbps

Before the fault happened I got 70mbps with the new static IP & 65 on the dynamic ones  I now am getting 38-40mbps - something could still be wrong

Download speedachieved during the test was - 43.9 Mbps
 For your connection, the acceptable range of speedsis 40 Mbps-45.4 Mbps .
 Additional Information:
 IP Profile for your line is - 45.4 Mbps

Upload speed achieved during the test was - 14.84Mbps
 Additional Information:
 Upstream Rate IP profile on your line is - 20 Mbps

[#2]

You probably have to give it 24-48 hours and possibly reboot your router(s), before the speed returns to normal.  If it doesn't contact Plusnet support.

[#3]

I believe this is already being discussed here: https://community.plus.net/t5/Phone/Ticket-130501872/m-p/1358875#M21752