To create a new default Snapshot, first create a Snapshot Template with your desired items and layout. This is done in the Advisor Portal > Templates > Snapshot tab. Then, navigate to the Client Settings > Client Groups tab, and select this template as the new default for one or both "default" groups:
Please note that this will only apply to newly created clients going forward in these respective client groups. For existing client plans, you must manually apply the new default in the Templates > Snapshot tab.
