My experience of upgrading from Select to Wealth, hope this helps:
I first tried this process in June/July 2023 and it was rejected. Tried the same again in December 2023 and it worked.
1. Mail to
banker@idfcfirstbank.com with reference to upgrade based on c2c along with other bank credit statement (credit limit > 5 lac, more the better)
2. They will ask for income proofs
3. Send them 3 months salary slip and salary account statement
4. I think they check for salary around 3 lac. per month
5. They might check your CIBIL report, especially how many recent credit card inquiries are there on your report.
6. If everything falls in place, your request will be approved.