In the Rulebook, it states that "The alliance can only build one level per action phase but may decide to build several sacred temples in the same action phase."
Does this mean that the alliance can build one level per "alliance turn" or that they are restricted to building one level per "day phase"? That latter would mean that it would take a minimum of three day phases to complete.
The Alliance can build one level per sacred temple per alliance turn.
The Alliance can for example begin 3 different temples during its turn.
Hope that helps.