Given what has been happening this week, has anybody seen this error in the wild (or others)? If so, will the order go inactive as with other similar errors?
This is not an error but an exchange rule that requires a Compliance check to see if Markets are halted before sending an order.
You will have to compare your error code to The IB Docs. The exchange sends out a code like “H” or “T1” etc.
Can you check in TWS whether that order is there? Though for unknown errors I send order cancellation via the API, then try resubmitting.
I don't have TWS open, I'm using the gateway. I haven't actually seen this error, I just want to be ready if I do get it.
I can tell you that I had orders with GAT parameter that were designed to go off during halt periods. They were simply executed when the market re-opened. I'm unsure how things would go for submitting during a halt. As always with stuff like this, write a test and wait for conditions. Asking support for this is a lottery, you're likely to get a random answer that is just a guess. For other instances you will just wait for 154 in your error handler and resubmit again and again. Or go fancy and read the halt times via some interface and sleep until that.