I purchased this cover from an online seller for its cachet, which consists of a
National Wildlife Federation cinderella, as it fits nicely in my
Mustelidae topical collection.

I cannot determine any significance to the date or location in the postmark, however. It seems clearly to be a philatelic usage, but is it relevant to the stationery (FDOI, etc.) or perhaps the cinderella? Did Mr. Orr just paste it to a cover and mail it to himself? The towns are
thirty miles apart, so that's not an unreasonable guess, but it seems a bit strange to me.
Any insight from the hive mind? What am I missing?