Drew I've just completed this Part 1 of a proposed 4 part series.

In the following article destined for a future Papua Philatelic Society "PNG Calling" bulletin I'm trying to establish early known usage for the three Geo. V overprinted stamps to aid in my research of some weird configured dates seen on numerous strikes of certain date-stamps.

If any member here can provide an earlier date than those seen in Table 1 below I would appreciate receiving a high resolution scan to confirm.