Invalid resource in copy source ARN - while copying between the same accesspoints

Question

I am trying to copy a file from a source access point to a destination access point with the same url except a different file names:

eg

aws s3 cp s3://arn:aws:s3:eu-west-2:1234567890:accesspoint:my-access-point-name/path/to/local-1234567890.inprogress s3://arn:aws:s3:eu-west-2:1234567890:accesspoint:my-access-point-name/path/to/local-1234567890

Giving:

copy failed: s3://arn:aws:s3:eu-west-2:1234567890:accesspoint:my-access-point-name/path/to/local-1234567890.inprogress to s3://arn:aws:s3:eu-west-2:1234567890:accesspoint:my-access-point-name/path/to/local-1234567890
An error occurred (InvalidArgument) when calling the CopyObject operation: Invalid resource in copy source ARN

Answer 1

Replacing : with / just before the access point name worked!

aws s3 cp s3://arn:aws:s3:eu-west-2:1234567890:accesspoint/my-access-point-name/path/to/local-1234567890.inprogress s3://arn:aws:s3:eu-west-2:1234567890:accesspoint/my-access-point-name/path/to/local-1234567890

Strange : is fine if one of the source or destination is access point ARN but not both.