Azure App Service "Scale Out" -- Instances Running Different App Versions?

Question

Originally asked at https://stackoverflow.com/questions/70194034/azure-app-service-scale-out-instances-running-different-app-versions but I did not get any responses.

I have a Dotnet 6 Web Application running on a Windows-based Azure App Service. As traffic grew, I took the recommendation to "scale-out" the app service to two instances. My deployments are done via a simple GitHub action and publish profile.

I've noticed that, by hitting the root API endpoint in which I return the build and server of the running API, that each of the two servers is running a different version of the code. When it builds and deploys next time, only one server reflects the newer version.

• name: Azure WebApp
  uses: azure/webapps-deploy@v2.2.3
  with:
  publish-profile: ${{ secrets.AZUREWEBAPPPUBLISHPROFILE }}
  app-name: esferas-app
  slot-name: staging
  package: ./artifacts/web

Is there something I'm missing? I couldn't find anything scouring the Azure or the GitHub Actions documentation for anything special required for scaling out on deploys.