They will hardly budge because I had even tried to first mail them and request for the conversion but in spite of holding a high value salary account, and one of their core cards with more than 10L limits, they did not convert. Asked them to reconsider their decision, still they didn't do anything.
Escalated from Escalations to Grievance to Priority still nothing happened, but just after initiating the conversation on that call, within 3 days, I got the email regarding successful conversion. So, try your luck playing with mails, but I would suggest you to avoid RM route as it would be time consuming and he would try to sell you some insurance, etc in exchange to get your work done and also is time consuming. Instead call their SM desk and make them remember your relationship value.