IME I was added as an AU in 2008 to an account that was opened in 2005. The AU on my report was dating back to 2005. BUT when I got my own AMEX last year it was backdated to 2008.
Im pretty sure that its from whenever you had a card with your name on it. I added my mother as a AU on my account recently and it turns out she had an amex for a few months in the 80's and they backdated her to then.
My mom has a business Amex that she's had for years (it's for her personal business with personal guarantee). I'm an AU on it.
If she gets a regular Amex will they back date it to her business date?.
Yes, the only cards that don't count for backdating are corporate.
Do I need to do anything or will the backdate come automatically?