East African Base Censor Marker Number I/01

[Ross Debenham]

I am in the process of obtaining a cover from East African Army Post Office 2 with the abovementioned censor marker on it. Proud lists the I prefix with the notation "Not seen in East Africa". Censor Type is EA B4. As prefix  II was used in Nairobi, III was used in Mombasa, IV in Berbera and V in Addis Ababa can any member assist me with the location of Base Censor I/01. I have seen this censor marker used once before, I believe. Attached is a scan of the envelope. Also attached is a scan of the sender name, etc on reverse of letter who would appear to be a member of the fleet air arm