In the unedited shot of Jackie walking from the airport telegraph desk to an airline ticket desk, the calendars on the walls near each desk are for obviously different months. One has 30 days and starts on a Sunday and one has 31 days and starts on a Saturday, so it is impossible for them to even be adjacent months.
When Joy and Jackie missed their departure on Flight 4, Jackie immediately tried to get them on Flight 5, which left only a few minutes later. Both planes were going to Hempstead and Toledo. It doesn't seem plausible that, even in 1948, two flights by the same airline would leave from the same airport for the same two destinations so close in time.
When Jackie sends the telegram from the airport, she misspells "grounded" as "grunded".