Many schools will continue to do post-December interviews. December 3rd is just an important date because the schools accept the students they believe to be "cream of the crop". So hopefully, you'll get more interviews post-Dec!
As to LECOM, there's only one part of the entire interview day that you need to be on top of your game for, which is the group interview. You'll be put into groups based on alphabetical order, and you'll be in a group with 5 other students, and 2 interviewers. Mine was laid back, but some others have said that they needed to fight for their chance to answer questions. Just be cordial, and be yourself. Too many people were so nervous that they were stuttering. So make sure you're calm and have answers prepared for the ones on the interview thread!
Good luck 🙂