A Unique First Day Cover: The 12 Anna Air-India International Inaugural Flight Stamp 1948

​A 12 anna postage stamp was released on 29 May 1948 which was unique in many aspects. This was valid only for use on mail sent on the first flight of Air-India International from Bombay to London via Cairo and Geneva on 8 June 1948. Special postal arrangements were instituted to ensure that mail from across India was accepted from 29 May to 5 June and processed solely for the 8 June inaugural flight.

​Here is a registered cover affixed with two of these 12 anna stamps, cancelled CAWNPORE,            29 MAY 48 addressed to Hamilton, Ontario, Canada. There is a MONTREAL / CANADA / 5 JUN 48 transit mark on the reverse and a HAMILTON / CANADA / 5 JUN 48 arrival mark on the reverse.
 
While we have recorded less than ten covers cancelled 29 May 48, this is the only one to have travelled out prior to the 8 June flight. This makes the cover unique and in a category by itself. It is also listed in Prafull Thakkar’s First Day Cover catalogue (2010) as #948.1.0a.
 
Inviting feedback on this and information on covers you may have with this stamp cancelled with a date prior to 8 June 1948.