And one more question if I may: is it possible to create multiple sub-accounts with IB to contain losses in the case of a mishap of this kind? Say 10 sub-accounts where one massive errors wipes out 1 sub-account leaving the other 9 intact?
Tonyf, I believe your fears of a portfolio wipe-out are unfounded as we have filters that should prevent large movements in stocks and the executions are done after the open. But if you are really shorting stocks that are HTB with very low volatility, you may want to rethink your strategy or perhaps look into hedging strategies if the potential for a blow out is probable. I followed up with our US office to confirm the US process. The buys are not pre-open or MOO. We notify clients there may be a closeout (reg 204. https://ibkr.info/article/3239) after 3:30 PM EDT and then again after the market close. The actual buy order is submitted at the open but depending on size it could be submitted as a VWAP or perhaps another algo. Note: the team does resolve the vast majority of issues and if you have hard to borrow shorts with reasonable size, contact the SLB customer service desk who will do their best to provide some color.
OK, will take it up with the "SLB" desk - how do I reach them? There is no SLB option when calling the IB helpline.
As for unfounded fears...this guy obviously would disagree: https://financefeeds.com/interactive-brokers-ex-customer-clash-access-source-code-materials/ I have no legal recourse to your "filters" - hence why I have to take control of the whole process.