Can you swap environment URLs with a retired environment?

I have an environment with a retired Amazon Linux platform and an environment with a Amazon Linux 2 platform I am trying to transition to. I followed the steps in the blue/green deployment guide but when I try to swap the environment URLs I get the error message:

You need at least two web tier environments in the Ready state to complete this operation.

The health is OK on both of them and neither have a database associated with the environment. Is Route 53 a requirement?