Using the offload to S3 wordpress plugin, all images are uploaded to AWS and the links replaced. The issue is that all sizes point to the same URL. But looking on the S3 panel itself I can see that different image sizes are uploaded. Here is an image object from WordPress.
Array
(
[title] =>
[image] => Array
(
[id] => 431
[alt] =>
[title] => night
=>
[description] =>
[mime_type] => image/jpeg
[url] => http://myamazonurl/wp-content/uploads/2015/09/14230510/night.jpg
[width] => 615
[height] => 409
[sizes] => Array
(
[thumbnail] => http://myamazonurl/wp-content/uploads/2015/09/14230510/night.jpg
[thumbnail-width] => 150
[thumbnail-height] => 100
[medium] => http://myamazonurl/wp-content/uploads/2015/09/14230510/night.jpg
[medium-width] => 300
[medium-height] => 200
[large] => http://myamazonurl/wp-content/uploads/2015/09/14230510/night.jpg
[large-width] => 615
[large-height] => 409
[test_size] => http://myamazonurl/wp-content/uploads/2015/09/14230510/night.jpg
[test_size-width] => 220
[test_size-height] => 146
)
)
)
I have also appended the sizes to the url like night-300×200.jpg but the resource is not found like this.
I am using Advanced Custom fields for the image field in question if that changes anything.