Received wisdom for the 'hard to get routes' is that you need to book them pretty much as the seats become available for booking. In other words, 350 days out.

If you're looking to travel in, say, October next year I'd look at triggering your AMEX so you get your voucher in time for this. It takes (IIRC) about 2 weeks from the trigger date to actually receiving the voucher.

Assuming you can be flexible about the dates you then can use the BA booking engine to search for 2 award seats on the dates you want (ie outbound and return). If you've not done this before, you need to log on to your EC pages and do a booking with miles. Not having enough miles isn't an issue - you can still search for availability. Once you've located the seats on the dates phone BA straight away and book them. They key to getting the seats you want is, I think, flexibility.

I don't know the answer to the rest of your questions (ie weather, best times to visit and so on) I'm afraid.

BAH