IWM Reddit Mentions | ChartExchange

Hey guys,
I am currently developing an automated trading strategy for Calendar Spreads (0 DTE) with BAG orders using the `ib_async` Python library and the TWS/IB Gateway API.
I have encountered a persistent issue regarding atomic bracket orders that include time-based conditions.
**The Problem:**
I am attempting to place an atomic bracket order (Parent Entry + Take Profit + Stop Loss + Time-based Exit). The Time-based Exit is intended to trigger a Market Close at a specific time on the following day. When I include any time-based logic (either `TimeCondition` in `order.conditions` or the `order.goodAfterTime` attribute) within the `BAG` bracket, the API rejects the entire order with: `Error: Field #6079: Illegal Value`.
**Observations and Analysis:**
1. **API vs. Mobile App:** The exact same order structure (Calendar Spread with a time-based condition for the next day) can be created and transmitted successfully via the IBKR Mobile App. The API, however, rejects it.
2. **Gateway Logs:** Logs from the IB Gateway show the following entry: `ComboRthOnlyGetter - RTH DISABLED: IWM - (1) IWM ... Calendar Spread`. This suggests that for certain `BAG` instruments, the API-side validator explicitly disables `outsideRth` support, even if the markets are currently open.
3. **Atomic Requirement:** Due to execution risk (legging risk), the entry and all protection orders (SL/TP) must be transmitted atomically. Splitting the combo into single legs is not a viable solution.
**What has been attempted:**
* **Protocol Symmetry:** Ensuring `order.conditionsIgnoreRth = True`, `order.conditionsCancelOrder = False`, and `order.outsideRth = True` are identical across all orders in the bracket.
* **Dummy Conditions:** Adding a `TimeCondition` set in the past to force the `ib_async` library to transmit the protocol flags for the conditions block (sequence `;1;0;`).
* **GAT Refactoring:** Replacing `TimeCondition` with `goodAfterTime` to avoid the conditions engine entirely.
* **RTH Synchronization:** Setting `outsideRth = False` to match the `ComboRthOnlyGetter` restriction.
In all cases involving a time-stempel for a future session, the API rejects the bracket as soon as it is linked to a `BAG` order. It appears the API validator for Combos does not allow orders to be "staged" for a future session if the instrument is flagged as RTH-only, whereas the Mobile App uses a different internal routing that bypasses this check.
**Question:** Is there any known way to submit an atomic bracket for a `BAG` order via the API that includes a time-based exit for the following day? Is this a documented limitation of the `BAG` validator in the TWS API, and are there any workarounds to achieve atomicity while maintaining a time-based exit?
Thanks for you input
\_framas\_