If content is returned to CloudFront from origin source, is it permanently cached in CloudFront from then on?
By default, CloudFront caches a response from Amazon S3 for 24 hours (Default TTL of 86,400 seconds). For more details you can refer to this AWS Documentation.
Hope this might help.
Hi Olamide, Ashok is correct. You can use the Cache-Control and Expires headers to control how long objects stay in the cache. Note that the minimum expiration time CloudFront supports is 0 seconds. The maximum value is 100 years