Notwithstanding any other provision of law to the contrary, the taxable year of an eligible person included in a composite return is the taxable year of the entity filing the composite return and the Maine adjusted gross income of an individual and the Maine taxable income of an estate or trust included as an eligible person in a composite return is that person's entity income for that taxable year.
18-125 C.M.R. ch. 805, § .08