It collects every priority shipped since the last release and writes a changelog summary in the rows' own words, so it matches the board.
01What a release is
02Cut one
Ask your agent. There's no cut button in the app, which only lists releases.
Your call: what the period is, and whether the summary says what you want customers to hear.
03What it doesn't do
It sends no customer notes and deploys nothing. See Telling customers.