Can I change my bid once I've submitted it?
Yes, you may. To increase the amount of a bid, simply enter a new bid with a higher bid amount. Since highest bids are accepted by the Seller, there is no need to rescind your first, or lesser, bid.
On the other hand, to decrease the amount of a bid, you must first rescind your original, or higher, bid, as described in the next question and answer. Then you may enter a new bid with a lesser bid amount.