API option to undo 'mark as shipped' not available

I have multiple clients that I provide API integration to/from Shipstation and I use the 'mark as shipped' option often.
(https://www.shipstation.com/docs/api/orders/mark-as-shipped/)

However, there is no option to undo this though the API. The only possibility is to manually go through each single order in the UI which, with hundreds to thousands of orders each day, is way too time consuming.

I'm not sure if this board is also for API requests, but even a batch undo 'mark as shipped' option in the UI would work for now.
And extra API endpoint would be better to automate it completely, but anything to avoid hours of work daily would work