WestJet is very strict on conditions with the Basic fare, as the restrictive conditions are the primary reason they can discount it to reach the lowest price. I would say based on other people’s experience expressed on social media, you have no chance of making any change. This is consistent with all airlines offering this type of fare - be sure that it is exactly as you want, or be prepared to just not use the ticket and buy another one if you need to make a change.

If a change is needed due to a medical emergency, death in the family or other reason out of your control, then travel insurance would be needed to cover your change costs, as this type of ticket won’t cover changes for any circumstances whatsoever.