The blessing mentioned is intended to make already active workshops get some extra materials, while also setting their progress to 100%, sending their cart pushers immediately after.
As of build 4.0.0.551-555598092 of Augustus, the blessing affects almost all workshops, regardless of employees, how recently they were built and even ignoring road access, making it so that the player can build several workshops right before the blessing and get its effects, opening itself for a heavy resource exploit. Even workshops that process materials not available on the map are impacted. Attached is a save file where this visibly happens (if the camera is not focused upon loading, the recently built workshops are on the far right of the city).
From testing, the only workshops I can tell are not affected are mothballed ones, which skip the blessing entirely, perhaps being the intended outcome for idle workshops during the blessing's timing.
This is probably unintended and potentially broken, and I therefore opened this case for this to be looked at.