IMO, it certainly started out as a legit enlisted M 1907/10 1GUR ulanka. Now, if the jacket was upgraded to officer, the cuff litzen would be appropriate, but the litzen on the collar is totally wrong. The single litzen bars shown on your ulanka is for the M-1915 Bluse of a grenadier infantry officer. The proper collar tabs would be a white wool rectangular patch with muted ( like the cuff) double litzen. Also, for an officer, you wouldn't have company/squadron buttons on the shoulder straps.
Dave