165.5. Notwithstanding any other provision of this division,(a) where a corporation to which section 165.3 or 165.4 applies, in this section referred to as “the first corporation”, has more than one taxation year ending in the same calendar year and is associated in two or more of those taxation years with another corporation that has a taxation year ending in that calendar year, the base level deduction of the first corporation for each taxation year in which it is associated with the other corporation ending in that calendar year is, subject to paragraph b, an amount equal to its base level deduction for the first such taxation year determined without reference to paragraph b; and
(b) where a corporation to which any of sections 165.2 to 165.4 applies, other than a corporation to which section 165.4.1 applies, has a taxation year that is less than 51 weeks, its base level deduction for the year is equal to that proportion of its base level deduction for the year, determined without reference to this paragraph, that the number of days in the year is of 365.