

From my collection attached is a non-stamped ( without franking ) cover sent from Buenos Aires , Argentina to Bordeaux, France in 1856.
The itinerary ( route) of this envelope has two legs , one by ship :Buenos Aires - Calais and another one by railway: Calais-Paris-Bordeaux , which can be traced by the place & date postmarks as well as by the text on cover's front as follows :
On front of the cover :
- On top side the handwritten text "
Par Le Packet anglais "
- An orange rectangular stamp with text :
COLONIES /A.M. 13 ( or "18" as it is not fully readable)
- Double-circle postmark : "12 NOV 56 / AMB.CALAIS " in black colour
On back of the cover :
- Double-circle postmark : "BUENOS AYRES / OC 1 / 1856 " in greyish-black colour ( It seems to be postmark of B.A. port post office ? )
- Double-circle postmark : "2E PARIS (60) / 12 NOV. 56 " - black
- Double-circle postmark : " PARIS / BORDEAUX 2 G - 12 NOV 56 " - black
- Double-circle postmark : " " BORDEAUX (32) / 13 NOV 56 " - black
And the last but not least postmark is also on the back , single-circle in greyish-black with text : "
H.P / NO - 11 / 1856 " .
So is this a maritime cancellation struck on board the English packet ( " Le Packet anglais " ) ?!? And which was this vessel doing the itinerary Buenos Aires - Calais in Oct/Nov. 1856 ?!?
Also what about the orange rectangular postmark (?) on the front cover ?!?
Thanks to everyone who can answer these questions