Add optional new parameters to existing payroll flow pattern

Summary:

We have a custom payroll flow which has 12 task lists from retro to end of payroll process. We need to add a new date parameter which is optional in prod. This is required because we use this payment date in BIP Report. Can you pls guide the correct process to add this new parameter in existing flow?

Will this have any impact to existing processes? Also how do we get this parameter data in BIP report?

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25C

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