You cannot change your address on your own on this primitive website. You have to "send a request" then wait. Also, they have some weird methods for you to add PBS money and book credit etc and then you have to separately for back and request the book. I'm sure they will have some story as to have it's a good cause, they're all volunteers etc.
You get what you pay for I guess.
Tip for consumers: Bye bye
Products used: Books..so far I've only sent books to them (other customers). When it's time to get my book things are so complicated. Whatever