After filing my tax returns and receiving a notice of assessment. I realized my employer made a mistake in the T4 he sent. I told him about it and he sent an amended T4 to CRA. I think CRA will take ages to do a reassessment. In order to prove my employment, I have a reference letter, amended T4 slip (without notice of reassessment ), and pay stubs. Would that be enough? or is Notice of Assessment (NOA) mandatory? Could my application get rejected if I send it without the NOA?