Originally Posted by
seaskybound
100£ change fee and since this would be last moment there would most probably be a hefty fare difference.
I am looking for tricks of the trade of a freebie change (e.g. if the late flight is pretty full it makes sense for them to send me earlier)
People's experience on here suggests that BA are almost always inflexible in such cases, unless as you say the later flight is overbooked and it is advatageous for them to move you.
All you can do is ask and hope for the best, chances are you will be disapointed but there is no harm in asking.