Is there a way to verify that my order is being held at IBKR ATS?

You can see that the order is being held at IBKR ATS using the mouse-over order status feature. To activate mouse-over order status help, go to Global Configuration (Edit menu in Classic; File menu in Mosaic) and in the left panel select Display and then select Settings. In the Tooltips section check "Show order status information."

To view the status of an order (including an order resting at IBKR ATS) hold your mouse over the order status field. 

Find out more in the IBKR ATS order page. 

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