We are in the process of upgrading to SDL 8 from SDL Tridion 2013 SP1. After the upgrade we would lie to delete old Publish target and use new Business process type to publish items. Are we required to republish all contents after decommissioning the old target? Will presentation side (website) continue to work without republishing all contents?
Website will work as expected, but CM will have lost the publishing status for the items, resulting in possible republishing mistakes (as the resolvers tend to calculate dependencies based on what was already published before).
This means dependencies will not be calculated correctly until all the publishing status are set - and hence the need to republish everything. I know there's work being done to automate this, I'll find the status of it tomorrow.