I assume you mean you are applying for residency positions.
If thats the case, ERAS should be said, done, and over with for this year. MPSE has already gone out. Some programs have a Nov 15th deadline for accepting applications. If you havent done so this year, I think its a bit late to be applying.
As for next year, I would ask your dean. I dont see why you couldnt apply, as long as you have completed or will complete all of your required course work by the start of your internship.