I applied to this site fairly close to the deadline and the TD replied. In my email, I acknowledged the limited number of on-site interview slots they have. This was his reply:
Dear Ms. XXXX, you are correct that we get more interview requests than we can meet, but we don't require visits at all, and many of our interns are accepted without visits since we depend completely upon the AAPI, by which we know everything about you but your shoe size and favorite color. We look forward to reading your application material, and phone interviews can easily be arranged. With best regards, John Linton
This was on December 2nd.