No charges if 1L not maintained, but I think you need to maintain basic MAB for that specific account variant, like 25K for Savings Max, 10K for Regular, etc & hence if balance below that basic MAB, charges will be applicable (Correct me if it's wrong)
For DC, account & card variant should match. If account variant changed, upgrade your card & you will get new card with the new account variant name and that will be free. (For Easyshop Platinum DC)