1.) Guessing from the author's own timeline (as much as Wikipedia can tell me) he in particular seems to have attended boarding school from the age of about 12 to 17 (changing between schools when he was about 14, but this seems to have been a family choice). Is it safe to assume the same time window for my MCs? Or would there be a slightly staggered age range?
2.) All I have to go on for this assumption is some of the photographs I've seen ( as well as my own school experience, thankfully less strict) and a modern conception of what "military school" connotes: short hair would be the norm for going into school, but how short? The intent with all regulated haircuts to go with uniforms seems to be obviously uniformity, but for younger boys would that be just short, sober male hair (without the worry that someone's going to run off and come back with a mohawk) or an actual buzz cut?
Terms Googled: Lots of permutations of "boarding school"/"military school"/"cadet"/"austria"/"hungary"/'19t