WM trades broken at the close

I had 200 shares of WM that sold with IB near the close. I then see an alert from tradestation that says ALL trades after 15:58 ET are broken.

nothing from IB (they will probably let me know in December) as of this post.

 

I noticed activity after the close. It was strange though.

 

The closing bell rang a minute early too...

 

SERIOUSLY???