Thanks for restoring the picture, Gilman.
Actually, this is a different picture of course, so the head-pattern is more clearly seen, and there remains no doubt this is OBP.
There is certainly variation in the breadth/type of streaking shown by this species. This bird seems to have broad streaks ('splodges' really), whereas a lot of pictures show much narrower streaks.
There seems to be less variation in the extent of streaking, after looking at just a handful of other images, admittedly. Relative to other locally occurring species it is quite extensive, with an area from the centre of the chest downwards and outwards where streaking is absent.
So to answer your question, no I don't think any local pipit species can be distinguished entirely on the underparts alone, these being variable within species.
Mike Turnbull