Unable to choose 'Existing Version' when trying to create a new environment

So I created a new environment based off an existing environment I had. I ran into an issue (I wasn't able to update the load balancer type to application load balancer), so I tried to create another new environment (aws documentation seemed to indicator I could only change the load balancer type during the creation of an environment).

But now, when I try to create a new environment, it won't let me choose 'Existing version'. I can either use the sample code, or upload an application. I thought to try eb create to choose an existing version, but this just created a new environment without the option to use existing version. Really confused as to why this is happening.