I've checked my BofA online payments for the past few months and they have all been electronic and delivered the next day. In fact I just made a payment to them late this evening (after the cutoff for delivery tomorrow) and it is showing they will receive payment on Thursday. I believe DC has two different cards- a "charge card" and a "credit card". I think mine is the "charge card" and does not allow for partial payments unless I make some arrangements. Perhaps BofA online payments are handled differently for each of these types of cards.