I hoped that the new documentation would also provide new information, which it did not for what I was looking for.
Specifically, if a cancel is submitted and the order has been partially filled, will status be PARTIALLY_FILLED, and will the executed quantity be accurate as of when the cancel was accepted (in other words, is the executedQty in the response GUARANTEED to be what Binance says it is, and is it GUARANTEED not to change (that of course means no further orders with the same newClientId are submitted).
There is another recent thread discussing problems with delayed responses when querying after an order is submitted, and that discussion causes some concern in this case. I would expect that the response to a successful cancellation to reflect the state of the system, and that information in the response should be gospel. But from the other thread, it is clear that Binance sometimes has a different view of what is important to traders. I think this case (cancelling an order with a reported partial executed quantity) is different and the right data should magically be used to create the response, but I would like that confirmed (as well as what the status would be).
Thanks