Different contributor here. Please permit me to assist.
Once a Chapter 13 plan is confirmed, the debtor and creditors are all bound by the plan orders. Unless the court expressly requires that you notify the trustee or the court of a change in your marital status, then you have no obligation to provide notice and you are free to divorce or legally separate, at your sole discretion.
There may be property issues that could be effected by a legal separation, such as determining who is ultimately responsible to pay a mortgage or other debt, which requires payment through or outside of the bankruptcy plan. However, as long as the payments are made timely, the plan will remain in force, and the trustee will have no reason to ask the court to modify the plan to account for the change.
Bottom line: satisfy the plan requirements, and you can simply continue as married, divorced, legally separated, etc. Fail to satisfy the plan requirements, and you risk a dismissal, plan modification request by the trustee or conversion to Chapter 7.
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