Method 1. Is there a mail program/server that will eliminate duplicate addresses in email sent to two mailing group lists with overlaying members? If yes, you can use that type of server and maintain separate lists for each unit, and email to two email group addresses.
Method 2: Set up four email address groups:
a. unit-1-only addresses
b. unit-2-only addresses
c. joint addresses (e.g. troop committee)
d. all addresses group which includes the three group address for unit-1-only, unit-2-only, and joint
Method 3: my.Scouting Announcements tool?
I suspect this tool currently designed for units that are not linked.
Email addresses can be downloaded from my.Scouting “Member Manager” for registered Scouts and Scouters. I do not know if non-registered parents can be linked to unit(s) or not.
There is a my.scouting Announcements tool & a my.Scouting Calendar tool (separate from Scoutbook). I have not used them.
my.Scouting Tools FAQs, September 2016
Q: What is Announcements and Calendar?
A: Both are tools Key 3s can use to post announcements and events specific to unit, district or council.
Q: Can I send out a calendar event or an announcement without clicking the Format Invitation button?
A: No, you have to format your invitation before sending it out to your unit or district.
Q: In the Calendar tool, when I schedule an event and select “Send Invitations”, how are people being notified?
A: The scheduled event will automatically appear in the member’s calendar in their My Organization Dashboard. Email notification will be in a future release.
Q: Why don’t I see an event I posted that occurs 6 months later?
A: Currently, the Calendar tool shows events posted within a two-month period. However, members in your organization are able to see events posted later than the two-month period in their My Organization Dashboard.