Many time you need to wait a long time before you get an upgrade offer. The best way is to check your eligibility in HDFC website, and see if there is any card of your liking and apply, it will automatically upgrade your current card. If you have an LTF, then take a screenshot of the eligible card (if paid) and send it to CC asking to upgrade your current LTF to the eligible LTF. 50-50 chance of success though