Originally Posted by KennyBSAT

The 37 day clock starts when the fee is charged by Citi, not when the account is opened or activated. The fee is reported to have posted as early as 2 days after the card arrives (rare) to 3 months after the card arrives (uncommon, happened to us once) to never (very rare).

Here's my TU score from Barclays. My first Exec card was opened in January '14. I opened 6 Citi cards and 10 other cards in 2014, after opening 18 in 2013. My score fell to 757 in July because I let a couple of cards' statements close with high utilization. I do have 10+ of years spotless credit history, mortgage, car loan, etc. I'm pretty sure you know this, but for anyone who sees it THIS IS NOT LIKELY POSSIBLE WITH A THIN CREDIT FILE.