If I were you I would leave the flaps in the same position they will be when you hunt, just my opinion.

I have a blind about 50 yards inside a woodline and it is a fresh setup. In the evenings deer stay in the field until after dark so last night I was in the field. Of course, I watched 3 deer go to the woods earlier than normal and they left on the trail going...RIGHT TO MY BLIND. They all snorted at it, and none of them ran from it. When the first deer snorted, the other deer were still in the field and rather than run or turn around, they immediately started walking to where the first deer snorted.

POINT:
Just causea deer snorts doesn't mean they smell you and they don't always run. If they can't smell you or can barely smell you, they will snort and investigate. If they see something unusual, they may snort. If that buck hasn't noticed that blind before, he may have been snorting at the blind. I have had them snort many times within 50 yards of my position, but not run from me.