The Menu button that appears at the bottom left of Releases can be set to one of three options -- MENU, MORE, or INFO.
This is selection is set as part of a Template Preset that is then assigned to a Release.
To navigate to Template Presets, click the hamburger menu at the top left of the Platform interface and find and click the Template Presets link.
This will take you to a list of existing template presets.
You can either click the name of an existing template to modify it, or click the Create A New One link to start a new one.
That will open a Template Presets options window. At the bottom of this settings page is a checkbox to select the Menu Option to display.
Select your preference, and then click the SAVE button at the upper right of the Platform interface.
Any Release that is assigned this Template Preset will now display this choice.
To learn about other Template Preset options and how to assign them to a release, see this document: Manage Template Presets