Yes, that's right really. You should check every morning, they appear around midnight / 1 am but it's usually only the initial launch time (355 days before departure) that people stay up to nab the released availability. Some people use Seatspy or Rewardflightfinder apps to track this, but if it's a limited search like this, it's easier to do it via BA.com. Some people find the BA app easier, and note that there is a separate BAEC app, which you can't use directly to book but does show availability in an efficient way. And check the BA App for the special POUG indicator (Limited Time offer) for the cash upgrades. It's not unusual, as you get nearer to departure, that they both become available. UuA (Avios upgrade) can even show on the day of departure. Finally there is AUP at the airport - this can be paid in cash or Avios, but the Avios exchange rate is silly, somehting like 0.7 pence per Avios.