Hi, thank you for using Intuit Turbo tax AnswerXchange
Turbo Tax has a great reference for refile:
https://turbotax.community.intuit.ca/community/tax-topics/help/what-is-refile/00/873779
You should definitely refile when you receive additional slips/ information after you file your tax return for the tax year. You can refile anytime after you receive your Notice of Assessment from your original filing.
When you refile you add information to your return and TurboTax will recalculate the whole return based on the original plus the added information. The whole return is then sent to the Canada Revenue Agency (CRA), not just the added information.
CRA will send a notice of Reassessment (NoA) after they process the refile. This will show the results before and after the new information is added. The NoA will show the result of the added information; either a refund or balance due.
Hope this helps