If you have ordered ‘new’ service yourself , and it’s necessary for a new pole to be placed on your property to provide your service, and the chosen location is near your wall , then the provider you have used ( BT ) have no responsibility for their supplier’s equipment ( Openreach ) , but you would have been consulted by OR about its location , if it we’re serving your property was to be sited on your ‘land’ for that purpose.
Its much more likely the pole is nothing to do with your existing service, and is being placed in a public area ( public footpath or verge the most likely place ) so OR have no need to advise you individually , although a pre- pole notice may have alerted you to its impending deployment .
If you are simply a concerned member of the public because you have seen the pre pole notice , and the pole is going to be near to a wall you own , the fact that you personally use BT as your supplier for broadband or telephone is irrelevant , it’s not going to be on your property, and for all you know the reason for the new pole may be driven by another providers customer ( like Sky or Talk Talk and not BT ) or it could simply be part of OR’s network expansion ( lots of new poles going up with the rollout of FTTP) so basically absolutely nothing to do with BT or any other service provider.
In the unlikely event that your wall is damaged by the installation of the pole , then OR are responsible for any restorative work , (should you need to report your wall as being damaged by the installation) but until it’s installed why assume the wall will be damaged ?, it almost certainly won’t be.
