You will have to wait for the automatic mirror update which will initialize installation packages, so you will be able to create a new installation package. Manual mirror update will not re-generate this container, which is normaly being used to create installation packages.
That is how the EA mirror works.
In some cases it can take more than 30 minutes even the mirror shows latest version.
The most important are two folders- distrib and instpackages.
Whenever you have new program version on the mirror, you have to create a new installation package and then run new deployment task which will create a new standalone setup package.