I am with TalkTalk and they themselves are worse than useless.
Report a fault and then its passed to Openreach who prioritise my fault for three days down the line.
BT faults take priority over other companies in most cases.
I was told it is BT who own the network and infrastructure and Openreach who do the consumer end.
In the middle they employ contractors to do the ground work IE digging and laying cables.
Just recently I was without a landline.
It took these clowns seven weeks to re-join a cable three houses along from my front door that they had damaged earlier.
They had managed to chop through the cable when replacing one of the junction boxes on the grass verge.
This cable fed all the houses/phones at my end of the street.
However, if you had not reported a fault, you were not re-connected no matter who your supplier was.
My neighbour who never reported a fault was without a landline for a further couple of weeks.
The excuse being they have too many faults and not enough linesmen.
But they have enough to be able to send two or three out to the same fault.
Around the corner there lives an Openreach linesman who never seems to be working. His van is there almost 24/7.
A couple of months ago they erected telegraph poles all over the place (in the 21st century) for Fibre Optic.
Thats all they have done. Ugly telegraph poles just acting as perches for birds because they have not been cabled to houses.