Sorry for the late reply, I've just returned! Unfortunately, I couldn't consolidate all my flights into a single OWA itinerary, so I had to take separate flights home. I tried to follow the advice to book flights first and adjust them later based on availability, but it seems I may have been overly optimistic and was not able to do this.
Now that I'm back home, I'm still left with flights for HND-HKG-SIN-SYD on my itinerary that I can't get refunded. Had to HUCA a few times to get someone that could help (and not say my ticket was only valid 1 year after booking and not my first departure), I've removed HND-HKG and changed HKG-SIN-SYD to July instead.
Although it didn't really work out for me in the end, I learned a lot from my first OWA booking attempt. In hindsight, it wasn't really worth it for me to try a OWA for a fairly simple itinerary, especially considering the minimal points savings (after change fees) and massive headache. Now, I'm still left with these extra flights that I need to figure out what to do with even though I promised myself I wasn't going to travel much this year!
Thanks heaps all for your help anyway, it's been a journey and a half haha
