still no real answer if i.r.e. (institute of radio engineers) received the article from shannon about information theory aka "a mathematical theory of communication" already in march 1940.

what the materials i found so far suggest is the following:

I.R.E. membership doubled in the decade 1927-1937, but actually quadrupled in the decade 1937-1947 ... As to the proceedings of the i.r.e., the members well know that the recent issues have exceeded in size any in the past history of the Institute, and have enabled reducing an embarrassingly large backlog of unpublished papers to acceptable dimensions. | the I.R.E. in I948* alfred n. goldsmith

the articles i have from 1948 tell mostly about a delay of one year by then. - on the other hand, the bibliographies in the radio progress report don't date further back than 1946, yet the committee states: "the fruits of war time research."

another hint maybe a conference in ny, which dealt with theories of the "relation between the bandwidth used by a communication system and its capacity to transmit information." shannon was there:

"Bandwidth vs. noise in communication systems." A review of a symposium before the New York Section of the I.R.E., November 12, 1947, on recent advances in the theory of communication participated in by A. G. Clavier, B. D. Loughlin, J. R. Pierce, and C. E. Shannon. Electronics, vol. 21, pp. 72- 75; January, 1948. | Radio Progress During I947

thanks for giving me access to those articles! where do i find "electronics vol21" ...