Thanks very much.

I called BT and they have indeed said that I was set up on the 40/10 profile, and he's put an order in to upgrade the line, which he says should happen within 24 hours.
hopefully, that will improve things.

Many thanks everyone.

And....

Who would have thought it?

He Didn't actually put through the order for me, So I've now done it online myself.
Hopefully, I'll get it at some point