Yes, that's annoying, especially if the market doesn't return...

Yes, that's annoying, especially if the market doesn't return and complete your order within a few days. But your broker should only charge you the $11 once per order. There should be no additional brokerage when the rest of the order is filled, even if you've amended it a dozen times in the process.

Of course, if you made your order "good for the day" then the balance will be cancelled and you end up getting stiffed for brokerage for the purchase of a single share. I never do "day" orders for that reason. I can cancel it myself after close if I want to and then I have the ability to keep it if I want.

But as a general rule I don't enter the auctions. They're a lottery.