No matter which payment option is enabled for customers, staff always have full control over payments inside Birrdi.
What Staff Can Always Do
Regardless of whether Pre-Payment is On, Off, or Store Card / Pay Later:
Charge a card manually
Mark a reservation as Pay Later
These actions are always available from the admin side.
Summary
Payment settings define the customer online experience, not staff capabilities.
Admins always retain full flexibility to manage payments as needed.