The Department shall determine the amount and duration of the REV Illinois Credit awarded under this Act, subject to the limitations set forth in this Act. For a project that qualified under paragraph (1), (2), (4), (4.1), or (5) of subsection (c) of Section 20, the duration of the credit may not exceed 15 taxable years, with an option to renew the agreement for no more than one term not to exceed an additional 15 taxable years. For a project that qualified under paragraph (3) or (3.1) of subsection (c) of Section 20, the duration of the credit may not exceed 10 taxable years, with an option to renew the agreement for no more than one term not to exceed an additional 10 taxable years. The credit may be stated as a percentage of the incremental income tax and training costs attributable to the applicant’s project and may include a fixed dollar limitation.
     Nothing in this Section shall prevent the Department, in consultation with the Department of Revenue, from adopting rules to extend the sunset of any earned, existing, and unused tax credit or credits a taxpayer may be in possession of, as provided for in Section 605-1055 of the Department of Commerce and Economic Opportunity Law of the Civil Administrative Code of Illinois, notwithstanding the carry-forward provisions pursuant to paragraph (4) of Section 211 of the Illinois Income Tax Act.