Is os2.0 support theme specific or store specific?

[Milind]

We are upgrading our application to support OS2.0 but are confused in the following question.

How do we identify whether this store is using the OS2.0 version or not? 

Is OS2.0 is theme-specific or it is store-specific?

We are following the documentation to identify 
https://shopify.dev/apps/online-store/verify-support

But quite confused in the documentation itself.

[Zworthkey]

@Milind 
You don't have to verify the theme is in  older version or OS 2.0.
if you uprader the app version it will work for both.

If you need more help regarding this. you contact to the Shopify Support team.
Might be their help you to figure out your Issues and confusion.
Thank you.