App Store - Are updates automatically released on approval?

As the question says, I am wondering whether UPDATED apps are automatically released onto the app store once they are approved?

My update is finished and has been tested, and as it takes a few days to approve I would like to submit it for approval now. In the meantime I need to change update a few things on my server, however I do not want the app update to go live until I have finished my server stuff.

Will the app go live immediately or do I get to choose the release date (after approval of course)?

Many thanks

Solution

You have an option to

choose the release date
release immediately on approval
once approved wait until I release it, (wait for you to click the release button so you can make server changes) aka Version Release Control.

This can all be done from iTunes Connect when submitting your application. However, if you select the option to "release when i'm ready" that application approval is only valid for that build. If you upload a new build, it must be re-approved.