Can you claim WHT on DA-1 for brokerage accounts opened and used while abroad?

Taxes
1

What I mean is that I have investments with a Canadian broker on mutual funds I bought while living in Canada. I still hold these investments, I just don’t pay into them anymore. Nevertheless, Canada deducts non-resident taxes on them.

Can I also report these on my DA-1 or am I only able to report the withholding taxes on the IBKR account and investments I made after I moved to Switzerland?

2

You can report your Canadian dividends on the DA-1 too.

As per the double tax treaty between Switzerland and Canada, the tax reclaim amounts to 15%.