I think that given how far in advance WMF Board meetings are planned, it should be possible to know the agenda and have the materials available for publication 2 weeks in advance.
If some last minute item comes up, it can easily be amended to the agenda. Similarly, if for some reason an agenda item is dropped or tabled for a future meeting, that can be done as well.
It is not my goal to box the Board into an unreasonably tight set of constraints. I think it should be possible to achieve the benefits of advance notification while maintaining a little flexibility to accommodate changes. Naturally, those changes should be publicized when they become known.
Pine