I also feed flock raiser with OS on the side. Have for many years, I have roo's so don't want them getting too much calcium. And I don't supplement light in the winter, those that take a vacation just get to rest. I have seen more of the calcium deposits on my EE eggs, once in a while on another breed, it's never been an issue. No idea why EE's might be more prone to that. I find my hens seem to do better on the flock raiser, the bit of extra protein seems to be a good thing for them. But, as said, do what works for you. I'd probably stick it out for a bit to see if things settle down, and then switch if you aren't happy with how things are going. Anytime you change feeds, either way, there will be an adjustment period.