I've been with Amex since 2011 opening a Delta Gold card with an initial SL of $1000. I've gradually increased that limit over time with a combination of phone CLI requests and AutoCLIs. For a few years I carried a high balance with them. For a while I was getting AutoCLIs every time I neared my limit. That debt-trap-gravy-train ran out at about $35k (and frankly, I'm glad it did... was a wakeup call for me!).
Of note, I put a LOT through this card... I've spent $60k+ per year for each of the last three years (and on track for that again this year). That Delta MQM bonus sure is nice...
Spent some time getting the finances in order and no longer carry a balance on any cards (finished that process around the end of 2017). Never late on anything... good mix of credit.
In February, with credit scores all above 800 and I tried for a CLI on the Amex web form. I started at $60k request and worked down slowly... they wanted 4506T for everything. (I gave up at $41k because a $5k increase wasn't worth being CLI-blocked for the next 6 months.)
Today decided to try again. Scores all 815+. Income stated $169,500. No 4506T request. Instant approval for $50k. (+$15k increase).
That's a hell of an SL up from the original $1000. :-)
