Originally Posted by craigthemif

You can't change the final destination of LHR. Moreover, Philippines Airlines don't fly from London to New York so I'm not sure how you would expect to be flown onwards from London. As mentioned, you simply buy another ticket (or use miles) to go wherever you want from London.

This ticket looks like a fully refundable and changeable ticket, but I have previously seen mistake fares where the airline will begrudgingly agree to honour the original fare, as long as the booking is converted to be inflexible.

Personally, I might want to change things to add a stopover in MNL as well, so by all means call PAL and see what they say, then report back here.