Just getting used to VS2012 publishing of Cloud Services. At present I have a one instance webrole which contains a MVC3 application. I can publish it to Azure without issue, and it creates the Cloud Service>Web Role>VMs. Fine. Takes a little while. 

However when I do a little code change how can I migrate just this code change without replacing all the VMs that implement the WebRole etc. 

It seems that Code and infrastructure are inseparable, or have I misunderstood. Is there a way to just update the code bit?

Thanks.