中加免税协议 international tax center 询问是否移民申请是否属歧视

各位好，又是报税季节。我是在加的国际留学生，根据中加免税协议 artical 19 china/Canada tax convention. 国际留学生收入是不收税的。依该条款，我询问international tax center, 被告知他们内部有一个规定（internal instructions）： 如果我递交了移民申请，这个条款就不适用。我认为这是一个歧视性的内部政策；
我把artical 19的原文附上。大家给点建议，1）看看他们的internal instructions 是不是歧视性政策和违反同时也藐视中国和加拿大的国际协定。2）我是否有权利据决告知他们我是否递交了移民申请.

Article l9
Students

Payments which a student, apprentice or business trainee who is, or was immediately before visiting a Contracting State, a resident of the other Contracting State and who is present in the first-mentioned Contracting State solely for the purpose of his education or training receives for the purpose of his maintenance, education or training shall not be taxed in that Contracting State.