Yes, you can make further changes to a confirmed booking. Previously, confirmation prevented further changes; this was changed to allow additional edits.
If the booking has been released, you can select UnRelease yourself before disbursement. Charges, fees and payments cannot be changed while the booking is released. Once it has been disbursed, it cannot be unreleased.
After additional changes, the booking moves to Check Bookings for you to review and reconfirm it.