Did Chase try to charge the OP any penalty interest charges or late payment fees? Doing so would probably break its own rules and could lead to regulatory action unless this contingency is clearly spelled out.

I also notice that the advertising merely says that you don't need to worry about late payments, not that Chase won't consider you to have failed to make payments or that your payments were late. OP didn't worry because he/she wasn't aware of any problem, nor should there have been a problem.