Day of travel change from direct to one-stop: reissue required?
I’m hoping those with more experience can provide a modicum of guidance re: a RTW flight change. One segment (but not the first segment) of my AONE5 is BA15, LHR-SYD direct with a brief refueling stop in SIN. BA15 departs LHR @ 21:45 while BA11 (direct LHR-SIN) departs LHR @19:05. With the intent of trying to spend more time in SIN, I was considering changing my RTW segment from BA15 to BA11 (LHR-SIN) + BA15 (SIN-SYD). I would try to make this change while transiting through LHR on the day of travel. Assuming there is F/A availability, the questions that arise: 1) would this necessitate a reissue? On one hand, there is no change to origin/destination/date of travel/stopover; OTOH it adds an additional segment to the JL-plated RTW, making my total segments 14 instead of 13. Or, since BA is the carrier, is there a day-of-travel alternative available to the agents because they operate the 2 flights in question? 2) There are varied reports regarding the BA ticket desk that would have the necessary expertise to handle this, i.e. transit desk vs First Class Check-in before security. Any personal experiences to suggest who I should approach first? Note: there is much discussion on the BA forum re: these specific flights but most is in relation to award travel or upgrades and none that I could find related to RTW tickets. Thanks in advance, even if your advice is to leave my itinerary alone because making this type of change would be asking for trouble.