Attempt to change service template using Change Service Template button fails with the error:
Error Cross-domain migration for Exchange subscription 1234567 is not possible because it contains emails on following shared domains: domain1.tld:domain2.tld. Remove all emails on shared domains firstly and repeat the operation.
Mailboxes on the mentioned domains are still included in some distribution lists
Use the following query to OA database to find the problem mailboxes:
select ds.*, c.* from exch_contacts_addresses ca inner join exch_contacts c on ca.contact_id = c.contact_id inner join domain_services ds on c.ds_id = ds.ds_id where ca.address like '%@domain1.tld' or ca.address like '%@domain2.tld'
select mailgroup_id, address_id, address from exch_mailgroups_addresses where mailgroup_id in (select mailgroup_id from exch_mailgroups where ds_id in (select ds_id from domain_services where subscription_id =SUB_ID)) and address like '%DOMAIN1' or address like '%DOMAIN2';
In Customer Control Panel find distribution lists by ID obtained using the query and switch to E-mail addresses tab: it will contain problem mailboxes. Delete them and repeat the attempt to change service template.