feedmail-ask-before-queue-default

feedmail-ask-before-queue-default is a variable defined in `feedmail.el'.
Its value is

"queue"

Documentation:
Meaning if user hits return in response to the message action prompt.
Should be a character or a string; if a string, only the first
character is significant. Useful values are those described in
the help for the message action prompt.

You can customize this variable.