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Me and my husband have multiple TRV in Canada valid until April 2018. However my husband plan to do post graduate study and already got an admission from a university in Canada. What will happen to his TRV if he will apply for a study permit? Are they going to cancel the TRV in exchange for the study permit?
Your husband actually needs a visa with the study permit, so having the multiple entry TRV actually removes the step of having to apply for one, so that should make the process easier.