google classroom – Hide my annotations before returing the assignment to all students

I’m using Google Classroom to schedule assignments to my students. When I correct them with the app in my tablet, a second file is generated with my annotations and corrections. This file seems available to the students from the very moment of its creation. This is inconvenient, because it does not allow me to double-check my annotations before sharing them with my students, and because not every student gets her/his feedback at the very same time.

I would want to annotate the student work, save my annotated file, and at some point make the annotations visible to all students at once. Does anyone know whether this is possible within Google Classroom?