I wouldn't trust the card's available balance because that is usually a day or 2 behind (like if you charge gas on Monday, it may not get posted until Wednesday or Thursday). When I use my card, I attach a sticky note on it to keep track of what I have spent. Be careful too if the day you plan for a debit falls on the weekend because that may change when the charge shows up. Another thing to try is to have your payments taken out of your checking account. Then you can keep track with the check register.

I'm afraid they will not cover the penalty because they took it out after the day you agreed. If they took it out before that date, you might have a better chance.