http://www.adslguide.org.uk/newsarchive.asp?item=2777
BT has announced a calendar of engineering work that will affect around 30
DSLAM's per night until October 2006. The schedule split down into regions
of the UK is shown below.

Central Midlands 4th September and 5th September
South Midlands 6th September
West Midlands 7th September
East Midlands 8th to 13th September
North Scotland 14th September
West Scotland 15th September to 18th September
East Scotland 19th September
Wales (North) 20th September
Northern Ireland 21st September
East Anglia 22nd September to 25th September
South Downs 26th September
Southampton 27th September
Severn Side 28th September
South Wales 29th September
North London 2nd October
South Longon 3rd October
Central London 4th October
North Downs 5th October
Thamesway 6th October
Mid Yorkshire 9th October
South Lancashire 10th October
Lancashire 11th October
Liverpool 12th October
Manchester 12th October
North East 13th October
Cornwal 13th October

The work is part of network upgrades and will occur between midnight and
6am, with people possibly experiencing a downtime of 30 minutes on the night
of the work. Therefore if your area is scheduled for work one evening and
your connection drops do not panic, but wait for a while before contacting
your providers support team. BT is also recommending that if after the
outage that you cannot reconnect that you switch your ADSL hardware off for
a minute and then switch it back on.