It'll be intersesting to see what ensues in the next few weeks. I have always observed the same, or similar behavior. Before I understood what was going on, I called this period "the buck shift". It always coincides with the velvet shedding period, if that helps you some. It is this situation that got me looking into Buck Dispersion - which is also impacting what you are observing.

Its not surprising that the mineral sites show less activity, even does and fawns should start ignoring them soon. I would still hope to photograph the older bucks in you better plots at night, but do not be surprised if you do not. Most of these 2-1/2-4-1/2 year old bucks are likely very active during the rut. It is this time of year when the establishment of Home Turf is expanded to areas measured in square miles, not acres. While a dominant deer may take up residence on your property, for 9 months of the year, it is possible that he could completely relocate to another area for the rut. Most bucks do not completely relocate however, though they will spend much less time in their core area than most think once they start expanding their range.

Once we get a frost or two, food plots will again be a little more attractive.