I have a LHR-FAO CE return booked for next week, both legs of which have been cancelled (even though they are still flying there). In MMB it is allowing me to rebook pretty much whenever I like. However, I don't know at the moment when I wish to travel. I would like to keep the booking active as it was a very good price. My question is, if I do nothing will I still be able to rebook even after the dates of the cancelled flights has passed?