Right now, all ATE emails are sent to HG primary user by default. However, other HG users can still respond to an ATE question but they have to do so from the portal. Subsequent emails will be sent to the HG user who most recently responded to a particular thread and then they are able to respond with the email links.
Provide an option for the HG to designate a default user who will receive the initial ATE emails if they want someone other than the primary user to get them.