My original Chase card was a AAA Chase card, and the credit limit somewhere around $5k. One month I spent $4k, and the limit spontaneously increased to $10.5k. The card was converted into a CSP, and I nearly maxed it out (went over $10k and within $500 of the limit) on a 3 week business trip overseas. No spontaneous limit increase that time, but when I called Chase to investigate why I wasn't getting UR points the next month, the rep offered to up the limit. I got immediate approval for over $20k.