Because you are a BT Business user you have a better SLA hence your compensation.
It is a well known on this forum that Openreach throttle when there is a capacity issue. When this happens it is usually resolved very quickly by extra capacity being added but has already been pointed out and in answer to your threads title, BT do not throttle connections.
Again as I said I know it is Openreach that do the throttling since my first call with BT so not sure why you keep telling me this. However my contract is with so I can only resolve with BT. The compensation is nothing to do with the SLA level. It was made at BT’s discretion as there is no liability in our contract. Think I also said that.
As for Openreach adding capacity that is no easy matter at our rural location so will probably be several months before they pull more lines. With all due respect that may not be the case in a large city.