EmberJS route design for multi-step workflow

I am trying to understand the best way to design a multi-step workflow;

So I have the following possibilities;

Step 1 (list) > Step 2a (review screen a) > Step3 (confirm screen)

Step 1 (list) > Step 2b (review screen b) > Step3 (confirm screen)

At each step, I call an API and based on the response, I make a decision. It is possible that user moves from Step 1 directly to Step 3 (based on API response)

OR it is also possible to have

Step 1 (list) > Step 2a (review screen a) > Step 2b (review screen b) > Step3 (confirm screen)

What is the best way to design the routes considering the above ? I mean in terms of nested routes, dynamic segments, folder structure for route objects, etc ?