I have read documentation on overwriting ArcGIS service via python. The overall process to programmatically overwrite service is to save a service definition draft, in the .sddraft file the set service type to from esriServiceDefinitionType_New to esriServiceDefinitionType_Replacement, then stage the .sddraft to a .sd file, and upload the .sd file.
What is the difference between setting the service type to from esriServiceDefinitionType_New to esriServiceDefinitionType_Replacement in the .sddraft file and setting it in the .sd file?
I ask this because I have several .sd files already created, and with a simple 7zip extraction I can open the .sd file and see the service type setting in the manifest.xml.
In theory I would like to make the service type change here in the .sd file, then upload and overwrite my existing service.
My current plan is to continue testing, and if all seems well, stick to this approach.
My environments: ArcGIS Server 10.3.1 & ArcMap 10.3.1