The above images and descriptions I received from Gene Labiuk, Canada. Apart from the black, purple and red colors there are indeed noticeable differences on the three markings like size of the characters, its spacing, thickness of characters and that of the box. The three strikes show no sign of wear so it is safe to rule out human intervention as a possible cause of the differences. Clearly Gene's observation that at least three different censors (or three different devices) were working or employed in Baguio at one time is correct.

This is probably an introduction to a much bigger picture. We are aware of the fact that the censorship of provincial mail throughout the Philippines, either philatelic, official or commercial, was handled by key provinces. It is therefore very highly possible that several devices were also used in many of the censoring provinces. With practically all the bases covered, the search for censor varieties could be the next in thing for the Japanese occupation period.