Benchmark testing in this case would not be advised. In the context of our program, these tests are just screeners. They are given on-grade to students in grades K-8. They are just screeners for identification purposes for teachers who may not know if their students are performing on-grade level or not. If you already know they are, then we suggest bypassing the benchmark tests and instead administer progress monitoring measures.
While we do not have a test to determine what grade your student is performing at. You start with a grade and a measure and go from there. Once a student is performing at the 50th percentile for a given grade/measure then they can be bumped up to the next grade where you want them to get to the 50th percentile and so on until the student is at their actual grade level.