Deductions & credits

Does that mean I fill in a W-9 now and then next calendar year I fill in a W-8BEN? At which time point or event trigger do I fill up the W-8BEN?

The bank warned me that the W-8BEN is what they should send me in accordance with IRS rules, so they believe that is what I should fill up. I am increasingly confused. I know I must fill in W-8BEN at some point, but I'm not sure exactly when I should do that. I'm not sure if W-8BEN should be tagged to the event of changing address, or to the tax calendar year.