Although set in 1944, when Andy Crewson and Gwinneth Livingston are on the cable car, you can see vehicles in the background through the window which are obvious early '50s models. When the cable car stops to allow passengers to disembark, there is a 1952 Pontiac on screen throughout the stop.
The large white sign at the military base at 4:02 has "Ordinance Bldg." at the top; that should no doubt be "Ordnance Bldg." (munitions or supplies, not a statute).
The aircraft shown flying off the carrier at the end of the film are Douglas AD-1s. They did not enter service until after the end of World War II.
The cargo aircraft said to be landing at "Honolulu-1944" in the opening scenes is a Boeing C-97 Stratofreighter, the prototype of which first flew on November 9, 1944, and the first production versions of which did not enter Air Force service until 1947.
It's 1944 when the fliers board the Catalina flying boat in Hawaii, but it has 1942-43 national insignia on the wings. Plain white stars on blue circles, missing the horizontal white stripes with blue border.
The aircraft shown flying off the carrier at the end of the film are Douglas AD-1s, and they carry postwar national insignia of a white star in a blue roundel, with white bars and a red stripe in each bar. They did not enter service until after the end of World War II.
The song "Rum and Coca Cola" can be heard playing on the jukebox in the hotel room. "Rum and Coca-Cola" was a hit in 1945, and this movie is set in 1944.
When Mississip offers a toast in the hotel room, he lists a string of places the Japanese could have ("as far as he is concerned"). Guadalcanal, the second place on the list, is poorly dubbed in to change the line, which originally listed Australia instead.