Hi to help you guys out BA can disuss any booking with passenger and credit card holder as long as you give name and then can confirm some security questions.
On a commercial booking with cash purchased direct with BA the passenger or cardholder can make changes provided they pay on a card in their name.
Im explaining this way because on an avios booking the executive club card holder who would have paid and used their points is the only one able to change the booking. Of course an executive club nominee can also discuss and make changes for thenmember on any abios or commercial booking where we see the exec member named.
On travel agency bookings its slightly different again. Typically the credit/debit card details including person paid doesnt show up in the booking so we would need to speak to the passenger to discuss or make changes.
****As a further note be aware that unless you select the person paying isnt travelling if you book on ba.com the cardholder name will default to the passenger. This then leaves us in the unfortunate situation where someone calls saying they are the cardholder but can we cant speak to them!!! Also this can look like fraud and therefore is taken very seriously and can cause serious problems for a passenger. So please be careful!*******
******** all opinions are my own and do not represent those of either BA or IAG*****