20. (1) Every foreign national, other than a foreign national referred to in section 19, who seeks to enter or remain in Canada must establish,
(b) to become a temporary resident, that they hold the visa or other document required under the regulations and will leave Canada by the end of the period authorized for their stay.
22. (1) A foreign national becomes a temporary resident if an officer is satisfied that the foreign national has applied for that status, has met the obligations set out in paragraph 20(1)(b) and is not inadmissible.
(2) An intention by a foreign national to become a permanent resident does not preclude them from becoming a temporary resident if the officer is satisfied that they will leave Canada by the end of the period authorized for their stay.
ただ"this does not authorize re-entry" の解釈について、この場合、一度延長ビザが再入国時無効になり、再審査・・・という解釈なら、どうなのでしょうね。たしか「ぐら」さんがどこかで解説して下さっていたと思うのですが。
(this does not re-authorize re-entryの記載があるのはワークなどでも同じ事ですが。)