Congrats isn't Tiffany's a hidden TL as well so utilization shouldnt factor in?
Yes, Tiffanys is hidden. It will only report to the 3 CRA's if in default.
Congrats OP, Ive had my card for a combined total (long story), for 12 yrs. As @FinStar stated earlier, They give you a "limit" to start with and to reference your purchases by, but as time goes on, you then call into credit and tell you you want to make a purchase, (if its over your limit), and they will either decline it, or let you. You can call in every 6 months to request a CLI.