The codes and winning do not have anything to do with each other in the way you're thinking they do. It's part of an ever changing security measure.
We've been through more than a few in PA...they now use a scan to win box for new instant tickets. They've mostly done away with letter codes,
I like the older ones that are still out there where I can check a code, at least you knew you had a winner by seeing letters: H, T, N, S, X, I, R, E etc.
Losers were: B, K, P, Q and a couple others.
If you're one of those players that play the game through and take the time to make sure you have a winning match either with numbers or
making words or whatever it is, then good but there is always the chance you miss something. I would just make sure that you're scanning your
ticket and waiting for the machine to tell you just how much you've won. Sometimes with some games, you don't see another win and you've
actually won more.
There are some people that scratched to find just the codes and didn't play the games or take the time to match numbers...they just look for
winning letter codes. These days, I've seen people scratch the box and run it through the scanner without even scratching any part of the play
area. I believe one of the reasons, which was weak at best, for changing things was to make people play their tickets. Duh. Once bought, you
should be able to do with it what the heck you want.....blow your nose on it, start a fire with it or NOT play it and just scan it.
To find the letters (I don't know what state you're in but I assume they are still using them where you are) you do have to scratch the whole
play area - they are usually scattered throughout that area.
Just play like you are don't worry about the codes, scan your tickets to double check things and good luck to you!