You are able to alter your destination, departure date, and arrival time with British Airways. The adjustments can be made over the phone or online.
Reminder: If you purchased your ticket directly from British Airways through their website, phone centre, or sales office, you cannot Change your flight online. You must speak with the third party directly if you made your reservation there.
To modify the time or date of your British Airways flight online:
the Manage My Booking link (it appears below the booking box)
Obtain your flight reservation as follows:
Please enter your last name and booking reference.
Select the Find My Booking link.
Choose the flight you want to modify.
Then select Change/Cancel Booking.
Make the required adjustments
Complete the prompts to finalise your new flight reservation.