I absolutly think that there is never a bad time to start a better mineral program. That being said, I also think that to get the most effect from a mineral for breeding you should start a good 5-6 months before you breed. Don't be discouraged or put it off by any means. It will still help and with more than conception. When our operation switched to the product you mentioned I saw an increase in body condition without any other input. The changes aren't instant but are valuable. While many factors affect breeding success without a strong mineral program you are starting from a deficit. Good luck and for what it is worth I think you are using as good of a product as there is.