I am using composer v.0.20.8 currently and I keep updating my .bna file. but every time I generate a new .bna file I have to teardown my fabric network and redeploy it.
Is there a way where I can just deploy it without tearing down my network in v.0.20.8 Composer?
Composer provides a upgrade utility to do just that. Please see the below link for reference.
Let us know if you get stuck in the process.