It's still tresspassing when you walk over there before the season starts. The only way to accomplish this without tresspassing is if you happen into your neighbor somewhere off his property, but again you aren't "taking care of this before season" with this method, you are merely relying on fate to bring both of you together. Unless of course you park at the person's entrance and "stalk" them waiting on them to come in and out. I don't see any issue there......