cgeoff

The pipits are certainly Rosy, not Olive-backed. The characteristic pale spot below the rear end of the supercilium is absent, indicating it is not Olive-backed. Overall, these pipits are too contrasting on the upperparts, and the olive fringes to the primaries are too strong.

Further, there is the date. In late August Olive-backed Pipits are still quite far north, though many will be on their way south. They don't reach HK until mid-late Sept.

Geoff