Dave is correct - summer availability to Europe can be a problem, especially if you don't have flexibility on dates and destinations. Coach availability will be better than Business or First Class. Availability will be greatest as soon as booking opens, at 330 days before the first flight. This means that you will want to have the miles in your account this summer, so that you can lock these tickets down. If there are 5 of you, that means that you need to receive 300,000 miles between now and summer for 5 coach tickets.
OOPS - there is a limit on the number of miles you can get per year on most credit cards, and the Citibank AAdvantage is one of those (I think it's 60,000 miles per year, but you better check it, it's never been a problem for me). I believe that the limit is waived for elites, so if this is going to be a problem (and it will become one pretty quick if you are pumping 60,000 miles/month through your card), whoever has the account these miles are going into better be elite either now or pretty fast.
I'll let others discuss the best ways to get around the total miles per year limit, I have read a few of those discussions but I wasn't paying much attention as it was strictly theoretical.
You can make these programs work for you, but they all have their rules, and you really need to know the rules to know when you need a strategy to work around them.
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