There is a section on ba.com re Umbrellas but as for golf umbrellas they'd be banned as cabin baggage as a blunt instrument and certainly at EDI you wouldn't get through security.

https://www.britishairways.com/en-gb...d-restrictions

You can take umbrellas and walking sticks (excl. hiking poles) in either your hand or checked baggage.

GOLF UMBRELLAS - If you carry your golf umbrella or parasol separately it will count as one item of your checked baggage allowance.