(b) waiving the right of the Commonwealth to recover from a person or health fund the whole or a part of an amount that the person or fund is required to pay to the Commonwealth under that section; or
(c) allowing a person who, or health fund which, is required to pay an amount to the Commonwealth under that section to pay that amount by such instalments as are specified in the determination.
(b) if no day is so specified--on the day on which the determination is made.