Don’t start to feed pollen patties to early. Only start pollen patties just prior to your natural pollen sources availability. And once you start continue until you see them bring in pollen on there own.
The reason, they will start to raise brood in high gear once they have pollen to feed the brood. If to early they will start consuming there food reserves at a much faster rate and could starve if the weather turns foul late in winter. Most bee hives starve around early March in our climate . Your hives are probably starting to raise small patches of brood but will control the rate because of pollen availability.
Beekeepers stimulate brood rearing by feeding pollen substitutes a few weeks prior to natural bloom to take advantage of better pollination. I do this for my blueberries because they bloom early in the season. But if you start to early the results can be catastrophic. Feeding sugar or syrup when the weather is warm enough is ok but timing is everything when it comes to pollen substitute.
The Busy Bee teaches two lessons: One is not to be idle and the other is not to get stung.