The next thing I'd look at is diet in your flock. What are you feeding them? What time last year did you set eggs, compared to this year? When I'm anticipating setting eggs, I pay extra attention to their diet, even giving them vitamins. My theory is this: while layer gives the flock the minimum nutrition needed to keep them fairly healthy, and produce eggs, it can be old, and the manufacturer is certainly not going to put more nutrient in the feed than to meet that minimum. And, after mill date, those nutrients begin an immediate down hill spiral in their quality. A well known poultry feed expert states that 42 days is the point when feed is transitioning from good feed to becoming rancid feed. Fermenting your feed actually produces some extra vitamins, though nothing can redeem a bag of rancid feed.
So, this might be a tad off topic, but is it a bad idea to buy in bulk such as in ton bags if it will last more than 6 weeks?