No, the bits got overriden when the next redeployment happens and there is no flag to switch the behavior. What's the use case here, why do you need to keep the old bits?
If you just want to keep the bits for all different versions of the application, there is a planned feature (application versioning) in v3 would help you. With that feature, all versions of the application bits will be stored in the application repository (with one specified version actively running).
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