The official period of use for the model 1930 definitives lasted 33 years, from the issue of the first stamps in 1930 to the end of 1962. During this long period, where humanity fought the second world war and the time following the war with a fast depreciation of the Finnish markka there are many short postal rate periods and a number of also otherwise interesting postal rates. One of the shortest rates is definitely the nine day air mail rate to the UK that was in force 19.2. – 27.2.1945. All items that I have seen from this short period consist of a foreign letter rate and an air mail rate:
Letter to abroad (outside the Nordic countries) 1.10.1942-30.6.1945 rate 4,50mk and air mail surcharge to the UK 19.-27.2.1945 rate 4mk/5g – alltogether nine days (restricted by the air mail surcharge rate).
Above we can see a letter posted during the nine day rate 19.-27.2.1945 on the 22.2.1945 to Blackwell (UK) from Tampere, air mail surcharge (<10g); total rate 12,50mk (4,50mk letter + 2 x 4mk air mail surcharges).
Above another item from the same period, posted on 20.2.1945 from Helsinki to London, returned to sender, because the addressee has not been reached. ”Gone away” written with a pencil on the cover with the postman’s signature and ”RETOUR” and ”PARTI” stamped on the cover. Cancelled when sent back in London SW 1, 5.3.1945. The cover has both Finnish and English censor strips (opened twice). The postage has been put together by using M30 definitive lions, 3pcs of 2mk yellow, 2pcs of 25p brown and one 5p brown, a total of 6,55mk. What we are seeing here is definitely not an item with the correct postage, still the letter definitely seems to have been delivered. The 5p stamp is made of cellulose paper and that also makes the item remarkable.
Combinations of surcharges during the nine day rate are possible, but as far as I know, no registered air mail has been found. This does not exclude the possibility of such covers lying around somewhere. There is also the possibility of air mail post cards, but the air mail post card rate has most likely been different for the period.
During the recent years there have been some of these nine day rate covers for sale in the various auctions, with near random sales prices – the prices have basically started from one hundred euro or little above and sales have taken place between the limit and close to 450€. In any case the rate seems not to be ”extremely” difficult to find, as there may have been a rather large number of letters sent to the UK during the period, including post from a number of companies.