I was there on Sunday and the post office was open. I bought stamps from Guest Services and then dropped off the postcards. They also have a mail slot I think to drop off the postcards. It usually takes 4-6 weeks to get them in Canada.
I'm thinking it was closed when that CM was there. Not unusual. The hours at the post office are extremely random. Most of the time it's closed, but once in a while it's open.
I can confirm it was open Sunday September 30th as well. DW and I mailed several postcards. Not sure what time it opened, but they said it was open until about 4 PM.
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