Had BT here on Friday, they have been coming since November. Installed a new master socket, a hybrid thingumyjig and a wifi repeater.
Convinced it has been even slower since and today it has been getting slower and slower.
Ran bleachbit (like CCleaner) and rebooted and it has taken ages to get anything going, especially the BT site, hasn't got into that at all.
I'm convinced it is the rain slowing down the internet electrons.