Individual (non-organization) accounts can only connect one set of social accounts per user. To use multiple social accounts, the user must convert to an organization and add an additional user.
Required steps
Create a Team (if already in a Team, select 'Manage Team.')
Invite a team member using any additional email address the account holder has access to. (This can be a secondary work email or personal email.)
Accept the invite and create the new user account.
Log in as the new user.
Create a Beacon (this Beacon can be deleted later).
Navigate to Social Media within the Beacon and connect the additional social account.
Log out and log back in as the original user.
Return to the Social Media section of any Beacon. A dropdown selector will now appear, allowing the user to choose between the different connected social accounts when adding posts.
Result
The original user can now select from multiple social accounts when adding posts to a Beacon.
Social accounts are available via the account dropdown in the Social Media section.