My Metroid and Zelda 1 carts both have the 1989 white seal on them (so both of these were obviously later issues), so I must have bought those titles during that year. The earliest ones (on both box and cart label) had the old 1985 circle seal on them. My Zelda 2 cart has the 1985 seal on its label.
Sometimes, the box and cart may have a newer seal, but in the instruction book the older seal turns up. A copy of Super Mario Bros. 2 (USA) that I have has the 1989 oval seal on the cart label, but has the 1985 circle seal inside the instruction book.
~Ben