Drop Ship Sales Order - Item Setup

Summary:

Drop Ship Sales Order - Item Setup

is this setup required at item level 'Default Sales Order Source Type' to set as 'External'?

We noticed items which is set up as 'Internal' also went to drop ship orders if we have 'Global Buy rule is setup for item or customer'

Referred the below document which doesn't have any item setup,

FA: SCM: OM: Describing the Drop Ship Process and Set up Requirements (KB110803)

Content (please ensure you mask any confidential information):

Version (include the version you are using, if applicable):

26A

Code Snippet (add any code snippets that support your topic, if applicable):