"My Info" section asks me for numbers associated with my wife's 2023 assessment. How would I have these numbers before she has even submitted her 2023 tax return?

You can enter an estimate to continue your return and then put in the correct amount when you have it.

That doesn't really make sense, because I won't receive my wife's 2023 assessment until after the tax return deadline.

When you don’t know your spouse's income and can’t find out through reasonable means, the Canada Revenue Agency recommends that you enter your best estimate. 

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