[quote=“seeker4”]This may not address your question directly, but still might be useful.
I got my ARC through Company 1 initially. Then, I wanted to change companies. I did change companies. Company 2 issued a letter of employment for me. Basically, it was just a letter stating that I was employed there, inclusive dates of the contract, etc. I took Company 2’s letter to the Foreign Affairs Police office in Ximen area. They simply made a notation on the back of my ARC that my employer had changed and that was that! 10 minute deal and no fee (as I recall).
Hope that helps.
Seeker4[/quote]
Thanks, seeker4. I forgot about this! 
The new laws state that you can add a second school to your ARC and then simply quit your first job. There was an excellent thread about this and how to do it. This means no visa run is necessary. 
Here’s the link: [Multiple schools on ARC?