I can speak with some authority on these matters as my wife and I have been trying to secure flights using AAdvantage miles over the last couple of weeks for a RTW trip to celebrate our silver wedding anniversary next year.
The big one for us is trying to get First Class across the Atlantic. We will be in Montreal but AA are great because they allow you to add on the Montreal / JFK leg to your itinerary with no extra points.
Firstly, don’t bother looking 360 days out unless you want to pay for their most “expensive” i.e. in points redemptions. The SAAver redemptions become available roughly between 9 & a 1/2 and 10 months out. They tend to be in slabs of Monday - Wednesday each week, although occasionally you can get a Thursday - Friday. Weekends seem to be hen’s teeth.
Secondly, don’t bother looking for First Class. If there is any, it will show up anyway in a Business Class search, and in addition if First Class does become available on a flight you’ve already booked in Business on, the beautiful people at AA will only charge you the points difference to upgrade.
Thirdly, I’ve looked at the next 12 months for the sector we need, and I think from memory there might have been 2 or 3 actual First Class seats available but 2 of them were at very short notice so don’t get your hopes up about enjoying First.
At least AA’s Business is lie flat across the Atlantic
Fourthly, AA has the most wonderful and helpful phone staff and as far as I can tell, they’re open 24/7. They can’t look at as many dates at once as you can by using their website, but they make up for that by being seemingly quite prepared to act as your travel agent. From Australia, their number is 00111 (800) 882 8880. I think there is a local number, but we have free calls to the USA, so I just call their USA number. The on hold time is generally reasonable too - mostly 10-20 min.
Finally, you may have noticed I haven’t mentioned BA in this response. There is stacks of BA availability both in Business and First but the fees (which are regularly as low as $6 per flight on AA) are extremely high, often over $500 per leg, so obviously I steer clear of them.
Sorry I can’t shed any light on CX (I book that through Asia Miles anyway) and I did try Finnair, but you can only check on that through an agent (i.e. not on their website), so it was just easier to do everything AA.
Of course their domestic is not a patch on their international… We are spoilt here in Oz
Regards and happy searching.