My DH has that same issue. He was approved for his first personal Amex card (Blue Sky) last July. His physical card shows a member date of 2013. However, his online Amex account has a member since date of 2008 (he had a corporate Amex in 2008). All three of his credit reports have his Blue Sky reporting as opened in 2008 (nice backdating for him!).
You should pull a credit report in a couple of months (after statements are generated) just to confirm that both are reporting as opened in 2012. More than likely, this will be the case.
Congrats on your new cards. Don't forget to ask for a 3x CLI on the Delta in 61 days from account opening.
FICOs: TU08 842 EQ08 850 EX08 850
My Wallet: Amex Gold NPSL; Amex Optima Platinum $25K; Amex BCE $12K; Apple Card $20K; BofA Travel Rewards Visa Sig $67.6K; Cap1 Quicksilver Visa Sig $10K; CSP $28.2K; Chase Freedom $13K; Chase Freedom Unlimited $21.4K; Citi Costco Visa $19.3K; Citi Double Cash $13.5K; Citi Simplicity Visa $23.3K; Discover IT $50K; Fidelity Visa $25K; NFCU Flagship Visa Sig $40K; NFCU More Rewards Amex $30K; PenFed Plat Rewards Visa Sig $50K; Sears MC $10.1K; US Bank Altitude Go Visa Sig $20K; US Bank Cash+ Visa Sig $26K; Wells Fargo Rewards Visa Sig $14K
