Question about contact details to pre-book oversize luggage.

The BA site suggests that you should advise in advance if you are bringing oversize equipment on, such as snow sports equipment (https://www.britishairways.com/conte...orts-equipment).

However, the link for "let us know" in the ski section takes you to the hotline for seating enquiries (https://www.britishairways.com/conte...SeatingBaggage). The section for contact us about baggage is online only.

Does anyone know who I should call at BA to tell them we are bringing oversize sports equipment so it doesn't get refused due to lack of space?