Hopefully you spoke to or wrote the theater director back and learned even more about the school’s program and thanked them for their time. I don’t think you can read into it beyond manners - but I do think it was nice of this teacher to reach out to you and bodes well about their engagement with the arts. This was a great opportunity for you to reiterate your interest in the school and program.
The deadline for your app was the 15th with schools getting ready to go into committee, so not odd timing at all,imo.