Adding Contacts with Department Field

Morning,

I work in a school which uses split delivery for our students and staff, the students are hosted externally.

What I would like to do is import the students into a address book so the staff can see their names. I have done this for around 50 of them by trial and error but I wondered if there is a Powershell command to do this. I currently use

Import-Csv c:\year13.csv|%{New-MailContact -Name $_.Name -DisplayName $_.Name -ExternalEmailAddress $_.ExternalEmailAddress -FirstName $_.FirstName -LastName $_.LastName}

Followed by

Get-Contact -ResultSize unlimited -Filter {(RecipientTypeDetails -eq 'MailContact')} | Set-MailContact -HiddenFromAddressListsEnabled $true

What I would prefer is the Import to

• Hide the contact from the global address book
• Add a field for Department so I can use the address book filtering to make one for each year at my school.

Can someone help please. The second command hide all contacts from the GAL so is a bit limited. I read somewhere that the 'hide from GAL' has been reinstated but I can't see it in the EAC.