이미 Blue Business Plus (BBP) 카드를 가지고 있습니다. 로그인을 했는데, Amex offers 배너로 

Apply for another Blue Business® Plus card, earn 50,000 Membership Rewards® points after you spend $15,000 in eligible purchases on the Card in the first 12 months of Membership.

이라 나옵니다. 

어플리케이션을 진행해봐도, Offer terms에 평생문구가 안 보입니다 (아래 붙임).

이런게 흔한 오퍼인가요? BBP카드 2개 가지고 계신 분 있으신가요?

You can earn 50,000 Membership Rewards^® points after you spend $15,000 or more (the "Threshold Amount") in eligible purchases on your Blue Business Plus Card within your first 12 months of Card Membership starting from the date your account is approved. Eligible purchases can be made by the Basic Card Member and any Additional Card Members on a single Card Account. Eligible purchases are purchases for goods and services minus returns and other credits. Eligible purchases do NOT include fees or interest charges, purchases of travelers checks, purchases or reloading of prepaid cards, purchases of gift cards, person-to-person payments or purchases of other cash equivalents. Limit one offer per Card Account. Offer may not be combined with any other special offer. Your account must not be canceled or past due at the time of fulfillment of any offers. The Membership Rewards points will be applied 8-12 weeks after the Threshold Amount is met.

If we in our sole discretion determine that you have engaged in abuse, misuse, or gaming in connection with the welcome offer in any way or that you intend to do so (for example, if you applied for one or more cards to obtain a welcome offer (s) that we did not intend for you; if you cancel or downgrade your account within 12 months after acquiring it; or if you cancel or return purchases you made to meet the Threshold Amount), we may not credit Membership Rewards^® points to, we may freeze Membership Rewards^® points credited to, or we may take away Membership Rewards^® points from your account. We may also cancel this Card account and other Card accounts you may have with us.

You can earn 50,000 Membership Rewards^® Points after you spend $15,000 or more on eligible purchases on your Card within your first 12 months of Card Membership starting from the date your account is approved. In rare instances, your period to spend $15,000 may be shorter than 12 months if there is a delay in receiving your Card. Also, purchases may fall outside of the 12 month period in some cases, such as a delay in merchants submitting transactions to us or if the purchase date differs from the date you made the transaction. (For example, if you buy goods online, the purchase date may be the date the goods are shipped).