There's a bunch in Warriors Apprentice that I can't reconcile without a lot of "everything going on is extremely illegal", like the stuff about Miles randomly swearing armsmen even though he probably shouldn't be allowed to due to quotas and that they aren't district men (this also comes up later with Mark and Elena, completely illegal, and Elena would know that, because he isn't actually in a legal position at that time which will allow him to accept oaths and there's no indication that there's an open slot for a new arms(wo)man). I also really have difficulties with the timeline, which is almost a year from start to finish, which I find complicated and complicating.

Oh, and I don't remember if the age is mentioned in WA or another book, but I think it comes down to Ezar being a few (four?) years older than Piotr, which makes me go "strange apprenticeship system you have there". But I just stumbled over that recently, so I'm still trying to track down if that's just me misremembering.