Question on buyins

[LittleDutch]

I just received the following notice from IB:

Please be aware that today is the first day that short stock sales transacted after the SEC's Emergency Order of 2008-09-18 will settle and become subject to hard T+3 close-out if the broker is unable to deliver the stock this afternoon. Your account has been identified as holding a short position as of the 2008-09-18 close and which therefore may be subject to buy in today in order to ensure IB's compliance with this Order.

We are currently in the process of determining what quantity of shares, if any, is available either internally or through third party borrows to meet our settlement obligation and will know that later today. We anticipate sending to you by approximately 12:00 PM Eastern Time a notice of your short positions which we are unable to cover and which will be bought in by IB if you fail to act and close our your short positions in a timely manner.

I've already closed all the short positions I had open on the 18th. Does this mean, as implied by the second paragraph, that I don't need to fear a buyin?

In general, can you be assured that you'll never face a buyin if you never hold a short position for more than three days?

Cheers,