One thing that I didn't mention about my line fault was it developed over time: for years the DSL wasn't affected by incoming calls, then towards the end of 2011 six or more rings of the phone would cause the DSL to drop and the router would resync almost immediately. Plusnet never "saw" these disconnections because they were so short and that made it really difficult to get anything done about it.
Also, at that time, the ticketing system at PN meant that adding to a ticket that hadn't been responded to by PN staff put the case to the back of the queue - this obviously made the whole experience incredibly frustrating!
Edit: Anyway a valuable lesson was learnt by me: to never get into a contract with an ISP for BB - a minimum term gives one more options, sadly for you though your choice is only based on 20CN kit (ADSL MAX) at the exchange...
Edited by 4M2 (Sat 27-Apr-13 12:07:02)