#Primary0 discussing

I am looking to update the Primary Department on the contact object based on the Program-Type that a prospective student chooses.

The example that I have is as follows: Student A applies for a Sport Management (Program-Type) which is part of our Business Department (University Department Record Type). The Primary Department on the Contact Object should then updated be to Business Department based off the specified Program Type.

Does anyone have any knowledge in using process builder, triggers, or workflows to complete this task?

When I do a search for an organization to see who are our affiliated contacts (people who have indicated the organization as their primary affiliation - employer, typically) - my search results are incomplete. For example I searched for an organization and the Account came back plus 5 Contacts - but not the primary contact. Both the contact and the account records show each other as the primary affiliation/contact - but why doesn't it show? Also, I get a different result if I put an asterisk at the end of the organization name for the search - even if it spelled EXACTLY as the Account Name (with and without the asterisk) - and the search is not setup to be exact matches only. Ideas? Is this a known issue? Thanks for any insight/help on this.

I don't know if people have the solution for this, but we are using the NPSP Address field, and we were using a default value for Primary Address Type field (the value was "Main Office"), well some of these places are homes and some are businesses so I was hoping to give it a null value. It seems that it won't let me do this. Any idea how I can give it a null value for Primary Address Type? 

Additionally... we use the Secondary Address Type field a lot without using the Primary Address Type, and again there is a trigger that causes Primary Address Type to put in a value if we were to use Secondary Address Type. 

Any suggestions? Thank you.