So all the addresses show plot numbers on the broadband company sites you looked at , but the Royal Mail site has the correct postal address , which seems odd as the Royal Mail is the organisation that supply’s the postal addresses to other companies that need a comprehensive set of national addresses ….although it’s not ideal if you want to swap providers why don’t you use the plot number ?
This mismatch , when it’s specifically Openreach based providers, is usually something that an ORDI ( Openreach data integrity) check can resolve, but it’s the current provider that would need to approach Openreach , you never answered if BT are your provider, BT would only be interested if you were their customer , so if it is BT you could contact them , although this isn’t a regular request so you may explain otherwise the representative may not be ‘au fait’ with this , obviously if BT are not your provider call whoever it is you use .
