21.4.9. Subject to sections 21.4.5, 21.4.8 and 21.4.11, if, in relation to any subject (in this section referred to as the “subject of an election made for Québec purposes”), an elector made a particular valid election under the particular provision before 20 December 2006, the particular provision must apply in respect of the subject of an election made for Québec purposes, as the particular provision read before that date, unless, after 19 December 2006, the elector makes, in relation to the subject of an election made for Québec purposes, a valid election under the provision of the Income Tax Act (R.S.C. 1985, c. 1 (5th Suppl.)) to which the particular provision refers, in which case the following rules apply:(a) the particular provision must apply in respect of the subject of an election made for Québec purposes, as the particular provision reads on 20 December 2006 and not as it read before that date; and
(b) the particular valid election is deemed never to have been made.