Well, I thought I was being smart waiting until Game Day to purchase some kids tickets because I was not sure if I needed two or three. Seems you cannot buy tickets two hours before tip-off online (?) so that waiting will cost me vs. the extra $5 had I went ahead and purchased 3 before today when I only needed two.
Only sharing so others know not to wait until close to the game to try to use a promo code online for the discounts. Live and learn. Still not sure why electronic, print-at-home ticket purchases have a cut-off time but at least I know now.