With categorical programs there's no need to worry because there's a internship tied in.
For the advanced programs, most of them have affiliated TY/IM programs that are local. Put in a little bit of work to research these programs. This can be easily accomplished by communicating with advanced PM&R program coordinators. Do this soon because the longer you wait... The more program coordinator will be.
Between the categoricals and TY/IM internships affiliated with advanced programs, you will have plenty of opportunity to match into a PGY-1. On top of that I would also learn about internships that are affiliated with your med school as a fallback plan.