Is this Warwick Streamer LX's neck screwed up?

[Chrisk-K]

I have only 3 days to evaluate a Streamer LX.

I set neck relief at around 0.3 mm. String height is slightly higher at the 12th fret than at the 24th fret, across all strings. The difference is about 0.1 mm. Shouldn't the opposite be measured if the neck has no issue? Unless the upper fret area is raised, how can action at the 12th fret be higher than action at the 24th fret? Thanks!