Originally Posted by Lussac

Couldn't make the change as you suggested might happen. I had the added complication in that any changes to the sectors on the SQ ticket should have been made by the original booking travel agent but they were totally unresponsive ('phone lines dead and no responses to other clients on social media email etc.) so in the end I managed to get through to SQ who took over the booking and rebooked me on LX1254 on the 5th April and, at the moment, that still seems to be scheduled to operate. Of course the added concern is that the BA flight might not take place although that too at the moment is still scheduled. As you said the fallback position if either LX1254 or BA 777 fail to operate is a new ticket at my expense from ZRH to LHR so just have to wait and see how it pans out.