@ HP,
Around here BT do use subcontractors to rod and then repair ducts (and sometimes damage existing cables) but they only use their own staff, including a man & wife team, to pull sub duct and then blow the actual fibre.
You can get a rough idea of the work planning process by using the web site:-
http://www.elgin.org.uk/specifying your area and radius but you MUST tick the Planned works in the top RH box as shown below.
It can be unreliable particularly if your area was originally installed with the more fragile salt glazed pipe ducts as nobody seems unduly concerned if the break them.
Once punctured tree roots colonise the duct for a plentiful supply of water.
This is the text for a typical fibre install:-
The Street, Wonersh, Guildford, Surrey
Works Start: 27 Aug
End: 27 Aug
Medium impact, delays possible
Location : Outside the Old Store The Street to junction Cranleigh Road...
Description: Access to Jointing chambers to provide new fibre cable off peak 09.30-15.30
Current status: Advanced planning
Kind regards,
Walter