I apologize if you already know this, but since it was news to me, I thought I would post.
Hen House posts their weekly ad on their website on Tuesday afternoon after 4pm.
Hy-Vee's ad is available on their website on Monday if you search by the city, Austin, MN. Please note that your store may have additional sales to the one's shown in the ad.
Personally, I'm a compulsive planner, so having the ads early is nice. It allows more time to search for coupons to match the sales.