Originally Posted by
alex67500
Leave it until you're clear on what you want to do (but don't let it get past 1 year after when the ticket was issued, otherwise your only option will be a refund). You don't have to accept a change now, and you only get one 'free' change.
Keep a note of the booking reference, and the e-ticket number (starting with 125- if you bought it from BA) in case it disappears from your online account.
Once you know when you want to get back, then phone in and get yourself rebooked.
One small point, once you have started a trip you have another 365 days to reschedule the return once the first flight is flown.
The date the ticket was issued is irrelevant, if it is booked as two one ways this doesn't apply.