Subscription not listed as available while trying to move a domain. If target subscription lacks any resource this should be detailed on UI
The move domain modal window should provide more information on why some subscriptions are not listed among the available ones because of different available resources than the needed by the "source" domains. This information can be found if the move is attempted over CLI but not from the UI, e.g.: "Unable to move the domain because the mail service is disabled on the target subscription."