Let’s recap in a way that sticks. Post office = closed. Private carriers = check their site. PO Box = you’re fine. Saturday = your new best friend. Good Friday = a day for chocolate, not errands. You can handle this.
Now, go enjoy your long weekend. Eat a marshmallow chick. Don’t think about stamps. The mail will wait. It’s patient. It’s paid for that. And if all else fails, just email them. Print it yourself. Cha-ching.