I live in the San Juan Islands in the US Pacific N.W. and planted my Sunshine Blue this spring in a container. It only had 10 or so berries which I understand is OK for a first year plant. It is flowering now (late Sept.). Should I remove the white flowers or let them be? I can't understand why it's flowering now. Any advice would be appreciated.
Fall flowering usually accompanies a warm spell, and some rain. You are in USDA hardiness zone 8, which is suitable for Sunshine Blue blueberry. It doesn't require the chill hours most blueberries do. That means that in autumn, if conditions simulate those in spring, the bushes will be prone to flower. This can decrease the productivity of the plant the next year, but removing them won't help. The more buds open now, the less you'll have next year. This is the worst in areas that consistently have long, warm falls.
There really isn't anything you can do about it. It's why all the major blueberry plantations are farther north. You will have to wait out this one, and hope for better luck in the future.