Both nominate and Anthus hodgsoni yunnanensis occur. Nominate is expected while A. h. yunnanensis is a rare migrant and winter visitor. They differ in the extent of dorsal streaking with A. h. hodgsoni much more heavily streaked. Flank streaks average narrower on yunnanensis. Canon PowerShot SX60 HS.
References:
Alstrom, P., K. Mild & B. Zetterstrom, (2003). Pipits and wagtails of Europe, Asia and North America. Identification and systematics. Princeton University Press, Princeton and Oxford.
Rasmussen, P.C. & Anderton, J.C. (2012) Birds of South Asia. The Ripley Guide. Vols. 1 and 2. Second Edition. Smithsonian Institution. Michigan State University & Lynx Edicions, Washington. D.C., Michigan & Barcelona.
Tyler, S. (2016). Olive-backed Pipit (Anthus hodgsoni). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/57801 on 21 July 2016).