I am not sure. NII started visit Mogilev in October of 1915, and by then, it was autumn and winter time. I have never seen him in pose like that from Mogilev visits. At least, in spring of 1916, he came to Tsarskoe Selo and in May came back to Stavka. It can be also Krasnoe Selo maneuvers, in 1913. ;-). Or 1914, no later, IMO. And, photo is very rare for me!