NIce!. I applied for the OYR clinical track as well. I also submitted March 1st and everything was completed March 20th.
The writing sample was about University-agency relationships and how their goals needs to be aligned and conducive to the success of future social workers. At least that it was I could grab from the article, there was more to it but it was time sensitive and a little rushed. I don't feel like my writing was strong enough or even adequately represented my writing skills and that was the whole point of the assignment. The interview itself went well, it is more conversational. She gave us scenario's and we were basically asked what we would do in that situation. Try to stand out and don't be nervous.
Good Luck!!