Update the Azure Marketplace on-boarded Azure Web App after deployment

I am planning to list my web application in azure market place.

I have applied for on-boarding process of my ARM template for listing in azure market place.

Currently I am releasing my first version of source in web app. I need to provide update of the source to customer for next release.

What are the options and ways are available for providing the updates to existing customers.

Start with the Azure Marketplace onboarding process and the ARM template deployment context described in the issue. Determine which update paths apply to an already deployed Azure Web App and document the supported process for delivering later source releases to existing customers.

Written by the indexing model from the issue text.