You won't find the 50,000 bonus mile offer for the Citi AAdvantage Platinum Select MasterCard on Citi's or American Airlines webpage.
You won't even find it on the major credit card affiliate blogs...because they won't get paid for it.
Instead you'll see an inferior offer for 30,000 bonus miles---which is not the deal you want to sign-up for!
Citi AAdvantage Select MasterCard 50,000 Sign-up Offer
Not to worry, the 50,000 offer is still alive and well if you look in the right place. There are still two working links for that you can apply for the card and earn the better welcome bonus.
That said, I can't say for sure but this offer may not be around for too much longer and it has been removed from both Citi's and AA's website. So, if you have been thinking about grabbing this card to earn 50,000 AA miles now may be a good time to do so.