Look at the available actions at the stages of the processes - with their help, I think you can solve your problem.
At a minimum, the actions of starting and ending the countdown are available, the creation of pending payments is the same.
As an option, you can try to set up a business process yourself, and to solve a specific problem, you can already ask a specific question.
If you want to have the business process customized to your requirements, you need to contact the integrators
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