When signing up for AMEX you get free lounge passes - does anyone know if supplementary card holders can sign up and get lounge access to?
https://www.americanexpress.com/nz/credit-cards/manage-your-…
And - does anyone have any insider tips on any banks offering a credit card signup bonus in the near future?

I can't find where it says, but I've not previously not been able to get lounge passes on the supplementary card