Lily,
As a follow on to my prior comment, the Active Message check box only applies to Member Notices that are automatically sent by groups.io in response to certain events.? So the Welcome notice sent by groups.io has this setting.? This allows you to have, for example, a draft Welcome notice or perhaps different Welcome notices and select which one is the Active one that groups.io is to use when a member joins.
The Note to Member notice is only sent manually by a mod/owner so there is no need for the Active Message flag (they are all 'Active' and available to be used by default).??
Toby
PS - I keep discovering more clever features of groups.io.. :)
Toby Kraft