https://www.canada.ca/en/immigration-refugees-citizenship/services/application/application-forms-guides/guide-5525-basic-guide-sponsor-your-spouse-partner-child.html#submit
It specifically says:
Application for spouses, common-law partners or conjugal partners currently living outside Canada and all dependent child sponsorships:
Case Processing Centre - Sydney
49 Dorchester Street
Sydney, NS
B1P 5Z2
Note: Choose this option if your spouse or common-law partner is living in Canada with you, but doesn’t plan to stay in Canada while the application is being processed.
This is the address for outland and applicants who are currently in Canada but will leave during the processing. This is if you're using a courier.
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If you're not using a courier, then this is the outland address:
Application for spouses, common-law partners or conjugal partners currently living outside Canada and all dependent child sponsorships:
Case Processing Centre - Sydney
P.O. Box 9500
Sydney, NS
B1P 0H5
Note: Choose this option if your spouse or common-law partner is living in Canada with you, but doesn’t plan to stay in Canada while the application is being processed.
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Read what it says in the title of each: living outside Canada. The note is just an additional note for applicants who are in Canada right now, but won't stay during the processing, so they will also be outside of Canada.