1129.80. For the purposes of section 1129.79, in computing the property income of a specified trust from the rental of specified immovables owned by the trust for a taxation year, a trust that becomes resident in Canada at a particular time is deemed to dispose, at the time (in this section referred to as the “time of disposition”) immediately preceding the end of the trust’s taxation year that ends immediately before the particular time, of each specified immovable then owned by the trust for proceeds of disposition equal to its fair market value at the time of disposition.