The beginning of the brinewall castle section (p 29) mentions, "While the castle walls allow its denizens a commanding view of the castle approach, no creatures guard the walls when the PCs first come to the castle."
Later, in area U1 (p 36), about the walls themselves, it says, "Three dire corbies stand guard here -- at any one time two of the creatures are walking lazy patrols along the walls to areas U3 and U5. Very little approaches the castle these days, so the first time the PCs approach, the dire corbies aren't being very attentive and take a -5 penalty on Perception checks to notice Intruders."
These statements seem contradictory to me, and I'm wondering how others have run this section, or how it was actually intended to work (or if I'm missing something here...).