Does that mean that they never re-use conid's? So you don't inadvertently?end up buying orange juice futures for instance or it will always return an error??
My approach to this problem is to send the order with the conid that you think is right. If the conid is no longer valid, you will receive an error message. Catch this error message by making a contract details query to IB (using symbol, exchange) and then use the result as the new conid. You can do this automatically in the code and it is fairly fast.
Good luck.
